diff --git a/daw-backend/src/audio/pool.rs b/daw-backend/src/audio/pool.rs
index d8db76b..73b7225 100644
--- a/daw-backend/src/audio/pool.rs
+++ b/daw-backend/src/audio/pool.rs
@@ -136,8 +136,8 @@ impl AudioFile {
             let peak_start = start_frame + peak_idx * frames_per_peak;
             let peak_end = (start_frame + (peak_idx + 1) * frames_per_peak).min(end_frame);
 
-            let mut min = 0.0f32;
-            let mut max = 0.0f32;
+            let mut min = f32::MAX;
+            let mut max = f32::MIN;
 
             // Scan all samples in this window
             for frame_idx in peak_start..peak_end {
@@ -152,6 +152,14 @@ impl AudioFile {
                 }
             }
 
+            // If no samples were found, clamp to safe defaults
+            if min == f32::MAX {
+                min = 0.0;
+            }
+            if max == f32::MIN {
+                max = 0.0;
+            }
+
             peaks.push(crate::io::WaveformPeak { min, max });
         }
 
@@ -549,13 +557,18 @@ impl AudioClipPool {
         entries: Vec<AudioPoolEntry>,
         project_path: &Path,
     ) -> Result<Vec<usize>, String> {
+        let fn_start = std::time::Instant::now();
+        eprintln!("📊 [LOAD_SERIALIZED] Starting load_from_serialized with {} entries...", entries.len());
+
         let project_dir = project_path.parent()
             .ok_or_else(|| "Project path has no parent directory".to_string())?;
 
         let mut missing_indices = Vec::new();
 
         // Clear existing pool
+        let clear_start = std::time::Instant::now();
         self.files.clear();
+        eprintln!("📊 [LOAD_SERIALIZED] Clear pool took {:.2}ms", clear_start.elapsed().as_secs_f64() * 1000.0);
 
         // Find the maximum pool index to determine required size
         let max_index = entries.iter()
@@ -564,12 +577,18 @@ impl AudioClipPool {
             .unwrap_or(0);
 
         // Ensure we have space for all entries
+        let resize_start = std::time::Instant::now();
         self.files.resize(max_index + 1, AudioFile::new(PathBuf::new(), Vec::new(), 2, 44100));
+        eprintln!("📊 [LOAD_SERIALIZED] Resize pool to {} took {:.2}ms", max_index + 1, resize_start.elapsed().as_secs_f64() * 1000.0);
 
-        for entry in entries {
-            let success = if let Some(embedded) = entry.embedded_data {
+        for (i, entry) in entries.iter().enumerate() {
+            let entry_start = std::time::Instant::now();
+            eprintln!("📊 [LOAD_SERIALIZED] Processing entry {}/{}: '{}'", i + 1, entries.len(), entry.name);
+
+            let success = if let Some(ref embedded) = entry.embedded_data {
                 // Load from embedded data
-                match Self::load_from_embedded_into_pool(self, entry.pool_index, embedded, &entry.name) {
+                eprintln!("📊 [LOAD_SERIALIZED]   Entry has embedded data (format: {})", embedded.format);
+                match Self::load_from_embedded_into_pool(self, entry.pool_index, embedded.clone(), &entry.name) {
                     Ok(_) => {
                         eprintln!("[AudioPool] Successfully loaded embedded audio: {}", entry.name);
                         true
@@ -579,8 +598,9 @@ impl AudioClipPool {
                         false
                     }
                 }
-            } else if let Some(rel_path) = entry.relative_path {
+            } else if let Some(ref rel_path) = entry.relative_path {
                 // Load from file path
+                eprintln!("📊 [LOAD_SERIALIZED]   Entry has file path: {:?}", rel_path);
                 let full_path = project_dir.join(&rel_path);
 
                 if full_path.exists() {
@@ -597,8 +617,12 @@ impl AudioClipPool {
             if !success {
                 missing_indices.push(entry.pool_index);
             }
+
+            eprintln!("📊 [LOAD_SERIALIZED] Entry {} took {:.2}ms (success: {})", i + 1, entry_start.elapsed().as_secs_f64() * 1000.0, success);
         }
 
+        eprintln!("📊 [LOAD_SERIALIZED] ✅ Total load_from_serialized time: {:.2}ms", fn_start.elapsed().as_secs_f64() * 1000.0);
+
         Ok(missing_indices)
     }
 
@@ -611,20 +635,29 @@ impl AudioClipPool {
     ) -> Result<(), String> {
         use base64::{Engine as _, engine::general_purpose};
 
+        let fn_start = std::time::Instant::now();
+        eprintln!("📊 [POOL] Loading embedded audio '{}'...", name);
+
         // Decode base64
+        let step1_start = std::time::Instant::now();
         let data = general_purpose::STANDARD
             .decode(&embedded.data_base64)
             .map_err(|e| format!("Failed to decode base64: {}", e))?;
+        eprintln!("📊 [POOL]   Step 1: Decode base64 ({} bytes) took {:.2}ms", data.len(), step1_start.elapsed().as_secs_f64() * 1000.0);
 
         // Write to temporary file for symphonia to decode
+        let step2_start = std::time::Instant::now();
         let temp_dir = std::env::temp_dir();
         let temp_path = temp_dir.join(format!("lightningbeam_embedded_{}.{}", pool_index, embedded.format));
 
         std::fs::write(&temp_path, &data)
             .map_err(|e| format!("Failed to write temporary file: {}", e))?;
+        eprintln!("📊 [POOL]   Step 2: Write temp file took {:.2}ms", step2_start.elapsed().as_secs_f64() * 1000.0);
 
         // Load the temporary file using existing infrastructure
+        let step3_start = std::time::Instant::now();
         let result = Self::load_file_into_pool(self, pool_index, &temp_path);
+        eprintln!("📊 [POOL]   Step 3: Decode audio with Symphonia took {:.2}ms", step3_start.elapsed().as_secs_f64() * 1000.0);
 
         // Clean up temporary file
         let _ = std::fs::remove_file(&temp_path);
@@ -634,6 +667,8 @@ impl AudioClipPool {
             self.files[pool_index].path = PathBuf::from(format!("<embedded: {}>", name));
         }
 
+        eprintln!("📊 [POOL] ✅ Total load_from_embedded time: {:.2}ms", fn_start.elapsed().as_secs_f64() * 1000.0);
+
         result
     }
 
diff --git a/lightningbeam-ui/lightningbeam-core/src/file_io.rs b/lightningbeam-ui/lightningbeam-core/src/file_io.rs
index a1644e6..3e188a1 100644
--- a/lightningbeam-ui/lightningbeam-core/src/file_io.rs
+++ b/lightningbeam-ui/lightningbeam-core/src/file_io.rs
@@ -139,104 +139,200 @@ pub fn save_beam(
     audio_pool_entries: Vec<AudioPoolEntry>,
     _settings: &SaveSettings,
 ) -> Result<(), String> {
-    // 1. Create backup if file exists
-    if path.exists() {
+    let fn_start = std::time::Instant::now();
+    eprintln!("📊 [SAVE_BEAM] Starting save_beam()...");
+
+    // 1. Create backup if file exists and open it for reading old audio files
+    let step1_start = std::time::Instant::now();
+    let mut old_zip = if path.exists() {
         let backup_path = path.with_extension("beam.backup");
         std::fs::copy(path, &backup_path)
             .map_err(|e| format!("Failed to create backup: {}", e))?;
-    }
+
+        // Open the backup as a ZIP archive for reading
+        match File::open(&backup_path) {
+            Ok(file) => match ZipArchive::new(file) {
+                Ok(archive) => {
+                    eprintln!("📊 [SAVE_BEAM] Step 1: Create backup and open for reading took {:.2}ms", step1_start.elapsed().as_secs_f64() * 1000.0);
+                    Some(archive)
+                }
+                Err(e) => {
+                    eprintln!("⚠️ [SAVE_BEAM] Failed to open backup as ZIP: {}, will not copy old audio files", e);
+                    eprintln!("📊 [SAVE_BEAM] Step 1: Create backup took {:.2}ms", step1_start.elapsed().as_secs_f64() * 1000.0);
+                    None
+                }
+            },
+            Err(e) => {
+                eprintln!("⚠️ [SAVE_BEAM] Failed to open backup: {}, will not copy old audio files", e);
+                eprintln!("📊 [SAVE_BEAM] Step 1: Create backup took {:.2}ms", step1_start.elapsed().as_secs_f64() * 1000.0);
+                None
+            }
+        }
+    } else {
+        eprintln!("📊 [SAVE_BEAM] Step 1: No backup needed (new file)");
+        None
+    };
 
     // 2. Prepare audio project for serialization (save AudioGraph presets)
+    let step2_start = std::time::Instant::now();
     audio_project.prepare_for_save();
+    eprintln!("📊 [SAVE_BEAM] Step 2: Prepare audio project took {:.2}ms", step2_start.elapsed().as_secs_f64() * 1000.0);
 
     // 3. Create ZIP writer
+    let step3_start = std::time::Instant::now();
     let file = File::create(path)
         .map_err(|e| format!("Failed to create file: {}", e))?;
     let mut zip = ZipWriter::new(file);
+    eprintln!("📊 [SAVE_BEAM] Step 3: Create ZIP writer took {:.2}ms", step3_start.elapsed().as_secs_f64() * 1000.0);
 
     // 4. Process audio pool entries and write embedded audio files to ZIP
-    // Smart compression: lossy formats (mp3, ogg) stored as-is, lossless data as FLAC
+    // Priority: old ZIP file > external file > encode PCM as FLAC
+    let step4_start = std::time::Instant::now();
     let mut modified_entries = Vec::new();
+    let mut flac_encode_time = 0.0;
+    let mut zip_write_time = 0.0;
+    let project_dir = path.parent().unwrap_or_else(|| Path::new("."));
+
     for entry in &audio_pool_entries {
         let mut modified_entry = entry.clone();
 
-        if let Some(ref embedded_data) = entry.embedded_data {
-            // Decode base64 audio data
-            let audio_bytes = base64::decode(&embedded_data.data_base64)
-                .map_err(|e| format!("Failed to decode base64 audio data for pool index {}: {}", entry.pool_index, e))?;
+        // Try to get audio data from various sources (in priority order)
+        let audio_source: Option<(Vec<u8>, String)> = if let Some(ref rel_path) = entry.relative_path {
+            // Priority 1: Check if file is in the old ZIP
+            if rel_path.starts_with("media/audio/") {
+                if let Some(ref mut old_zip_archive) = old_zip {
+                    match old_zip_archive.by_name(rel_path) {
+                        Ok(mut file) => {
+                            let mut bytes = Vec::new();
+                            if file.read_to_end(&mut bytes).is_ok() {
+                                let extension = rel_path.split('.').last().unwrap_or("bin").to_string();
+                                eprintln!("📊 [SAVE_BEAM] Copying from old ZIP: {}", rel_path);
+                                Some((bytes, extension))
+                            } else {
+                                eprintln!("⚠️ [SAVE_BEAM] Failed to read {} from old ZIP", rel_path);
+                                None
+                            }
+                        }
+                        Err(_) => {
+                            eprintln!("⚠️ [SAVE_BEAM] File {} not found in old ZIP", rel_path);
+                            None
+                        }
+                    }
+                } else {
+                    None
+                }
+            }
+            // Priority 2: Check external filesystem
+            else {
+                let full_path = project_dir.join(rel_path);
+                if full_path.exists() {
+                    match std::fs::read(&full_path) {
+                        Ok(bytes) => {
+                            let extension = full_path.extension()
+                                .and_then(|e| e.to_str())
+                                .unwrap_or("bin")
+                                .to_string();
+                            eprintln!("📊 [SAVE_BEAM] Using external file: {:?}", full_path);
+                            Some((bytes, extension))
+                        }
+                        Err(e) => {
+                            eprintln!("⚠️ [SAVE_BEAM] Failed to read {:?}: {}", full_path, e);
+                            None
+                        }
+                    }
+                } else {
+                    eprintln!("⚠️ [SAVE_BEAM] External file not found: {:?}", full_path);
+                    None
+                }
+            }
+        } else {
+            None
+        };
 
-            let format_lower = embedded_data.format.to_lowercase();
-            let is_lossy = format_lower == "mp3" || format_lower == "ogg"
-                        || format_lower == "aac" || format_lower == "m4a"
-                        || format_lower == "opus";
+        if let Some((audio_bytes, extension)) = audio_source {
+            // We have the original file - copy it directly
+            let zip_filename = format!("media/audio/{}.{}", entry.pool_index, extension);
 
-            let zip_filename = if is_lossy {
-                // Store lossy formats directly (no transcoding)
-                format!("media/audio/{}.{}", entry.pool_index, embedded_data.format)
-            } else {
-                // Store lossless data as FLAC
-                format!("media/audio/{}.flac", entry.pool_index)
-            };
-
-            // Write to ZIP (uncompressed - audio is already compressed)
             let file_options = FileOptions::default()
                 .compression_method(CompressionMethod::Stored);
 
             zip.start_file(&zip_filename, file_options)
                 .map_err(|e| format!("Failed to create {} in ZIP: {}", zip_filename, e))?;
 
-            if is_lossy {
-                // Write lossy file directly
-                zip.write_all(&audio_bytes)
-                    .map_err(|e| format!("Failed to write {}: {}", zip_filename, e))?;
-            } else {
-                // Decode PCM samples and encode to FLAC
-                // The audio_bytes are raw PCM samples (interleaved f32 little-endian)
-                let samples: Vec<f32> = audio_bytes
-                    .chunks_exact(4)
-                    .map(|chunk| f32::from_le_bytes([chunk[0], chunk[1], chunk[2], chunk[3]]))
-                    .collect();
+            let write_start = std::time::Instant::now();
+            zip.write_all(&audio_bytes)
+                .map_err(|e| format!("Failed to write {}: {}", zip_filename, e))?;
+            zip_write_time += write_start.elapsed().as_secs_f64() * 1000.0;
 
-                // Convert f32 samples to i32 for FLAC encoding (FLAC doesn't support f32)
-                // FLAC supports up to 24-bit samples: range [-8388608, 8388607]
-                let samples_i32: Vec<i32> = samples
-                    .iter()
-                    .map(|&s| {
-                        // Clamp to [-1.0, 1.0] first, then scale to 24-bit range
-                        let clamped = s.clamp(-1.0, 1.0);
-                        (clamped * 8388607.0) as i32
-                    })
-                    .collect();
+            // Update entry to point to ZIP file
+            modified_entry.embedded_data = None;
+            modified_entry.relative_path = Some(zip_filename);
 
-                // Configure FLAC encoder
-                let config = flacenc::config::Encoder::default()
-                    .into_verified()
-                    .map_err(|(_, e)| format!("FLAC encoder config error: {:?}", e))?;
+        } else if let Some(ref embedded_data) = entry.embedded_data {
+            // Priority 3: No original file - encode PCM as FLAC
+            eprintln!("📊 [SAVE_BEAM] Encoding PCM to FLAC for pool {} (no original file)", entry.pool_index);
+            // Embedded data is always PCM - encode as FLAC
+            let audio_bytes = base64::decode(&embedded_data.data_base64)
+                .map_err(|e| format!("Failed to decode base64 audio data for pool index {}: {}", entry.pool_index, e))?;
 
-                let source = flacenc::source::MemSource::from_samples(
-                    &samples_i32,
-                    entry.channels as usize,
-                    24, // bits per sample (FLAC max is 24-bit)
-                    entry.sample_rate as usize,
-                );
+            let zip_filename = format!("media/audio/{}.flac", entry.pool_index);
 
-                // Encode to FLAC
-                let flac_stream = flacenc::encode_with_fixed_block_size(
-                    &config,
-                    source,
-                    config.block_size,
-                ).map_err(|e| format!("FLAC encoding failed: {:?}", e))?;
+            let file_options = FileOptions::default()
+                .compression_method(CompressionMethod::Stored);
 
-                // Convert stream to bytes
-                use flacenc::component::BitRepr;
-                let mut sink = flacenc::bitsink::ByteSink::new();
-                flac_stream.write(&mut sink)
-                    .map_err(|e| format!("Failed to write FLAC stream: {:?}", e))?;
-                let flac_bytes = sink.as_slice();
+            zip.start_file(&zip_filename, file_options)
+                .map_err(|e| format!("Failed to create {} in ZIP: {}", zip_filename, e))?;
 
-                zip.write_all(flac_bytes)
-                    .map_err(|e| format!("Failed to write {}: {}", zip_filename, e))?;
-            }
+            // Encode PCM samples to FLAC
+            let flac_start = std::time::Instant::now();
+
+            // The audio_bytes are raw PCM samples (interleaved f32 little-endian)
+            let samples: Vec<f32> = audio_bytes
+                .chunks_exact(4)
+                .map(|chunk| f32::from_le_bytes([chunk[0], chunk[1], chunk[2], chunk[3]]))
+                .collect();
+
+            // Convert f32 samples to i32 for FLAC encoding
+            let samples_i32: Vec<i32> = samples
+                .iter()
+                .map(|&s| {
+                    let clamped = s.clamp(-1.0, 1.0);
+                    (clamped * 8388607.0) as i32
+                })
+                .collect();
+
+            // Configure FLAC encoder
+            let config = flacenc::config::Encoder::default()
+                .into_verified()
+                .map_err(|(_, e)| format!("FLAC encoder config error: {:?}", e))?;
+
+            let source = flacenc::source::MemSource::from_samples(
+                &samples_i32,
+                entry.channels as usize,
+                24,
+                entry.sample_rate as usize,
+            );
+
+            // Encode to FLAC
+            let flac_stream = flacenc::encode_with_fixed_block_size(
+                &config,
+                source,
+                config.block_size,
+            ).map_err(|e| format!("FLAC encoding failed: {:?}", e))?;
+
+            // Convert stream to bytes
+            use flacenc::component::BitRepr;
+            let mut sink = flacenc::bitsink::ByteSink::new();
+            flac_stream.write(&mut sink)
+                .map_err(|e| format!("Failed to write FLAC stream: {:?}", e))?;
+            let flac_bytes = sink.as_slice();
+
+            flac_encode_time += flac_start.elapsed().as_secs_f64() * 1000.0;
+
+            let write_start = std::time::Instant::now();
+            zip.write_all(flac_bytes)
+                .map_err(|e| format!("Failed to write {}: {}", zip_filename, e))?;
+            zip_write_time += write_start.elapsed().as_secs_f64() * 1000.0;
 
             // Update entry to point to ZIP file instead of embedding data
             modified_entry.embedded_data = None;
@@ -245,8 +341,17 @@ pub fn save_beam(
 
         modified_entries.push(modified_entry);
     }
+    eprintln!("📊 [SAVE_BEAM] Step 4: Process audio pool ({} entries) took {:.2}ms",
+              audio_pool_entries.len(), step4_start.elapsed().as_secs_f64() * 1000.0);
+    if flac_encode_time > 0.0 {
+        eprintln!("📊 [SAVE_BEAM]   - FLAC encoding: {:.2}ms", flac_encode_time);
+    }
+    if zip_write_time > 0.0 {
+        eprintln!("📊 [SAVE_BEAM]   - ZIP writing: {:.2}ms", zip_write_time);
+    }
 
     // 5. Build BeamProject structure with modified entries
+    let step5_start = std::time::Instant::now();
     let now = chrono::Utc::now().to_rfc3339();
     let beam_project = BeamProject {
         version: BEAM_VERSION.to_string(),
@@ -259,8 +364,10 @@ pub fn save_beam(
             audio_pool_entries: modified_entries,
         },
     };
+    eprintln!("📊 [SAVE_BEAM] Step 5: Build BeamProject structure took {:.2}ms", step5_start.elapsed().as_secs_f64() * 1000.0);
 
     // 6. Write project.json (compressed with DEFLATE)
+    let step6_start = std::time::Instant::now();
     let json_options = FileOptions::default()
         .compression_method(CompressionMethod::Deflated)
         .compression_level(Some(6));
@@ -273,10 +380,15 @@ pub fn save_beam(
 
     zip.write_all(json.as_bytes())
         .map_err(|e| format!("Failed to write project.json: {}", e))?;
+    eprintln!("📊 [SAVE_BEAM] Step 6: Write project.json ({} bytes) took {:.2}ms", json.len(), step6_start.elapsed().as_secs_f64() * 1000.0);
 
     // 7. Finalize ZIP
+    let step7_start = std::time::Instant::now();
     zip.finish()
         .map_err(|e| format!("Failed to finalize ZIP: {}", e))?;
+    eprintln!("📊 [SAVE_BEAM] Step 7: Finalize ZIP took {:.2}ms", step7_start.elapsed().as_secs_f64() * 1000.0);
+
+    eprintln!("📊 [SAVE_BEAM] ✅ Total save_beam() time: {:.2}ms", fn_start.elapsed().as_secs_f64() * 1000.0);
 
     Ok(())
 }
@@ -296,23 +408,32 @@ pub fn save_beam(
 /// # Returns
 /// LoadedProject on success (with missing_files list), or error message
 pub fn load_beam(path: &Path) -> Result<LoadedProject, String> {
+    let fn_start = std::time::Instant::now();
+    eprintln!("📊 [LOAD_BEAM] Starting load_beam()...");
+
     // 1. Open ZIP archive
+    let step1_start = std::time::Instant::now();
     let file = File::open(path)
         .map_err(|e| format!("Failed to open file: {}", e))?;
     let mut zip = ZipArchive::new(file)
         .map_err(|e| format!("Failed to open ZIP archive: {}", e))?;
+    eprintln!("📊 [LOAD_BEAM] Step 1: Open ZIP archive took {:.2}ms", step1_start.elapsed().as_secs_f64() * 1000.0);
 
     // 2. Read project.json
+    let step2_start = std::time::Instant::now();
     let mut project_file = zip.by_name("project.json")
         .map_err(|e| format!("Failed to find project.json in archive: {}", e))?;
 
     let mut json_data = String::new();
     project_file.read_to_string(&mut json_data)
         .map_err(|e| format!("Failed to read project.json: {}", e))?;
+    eprintln!("📊 [LOAD_BEAM] Step 2: Read project.json ({} bytes) took {:.2}ms", json_data.len(), step2_start.elapsed().as_secs_f64() * 1000.0);
 
     // 3. Deserialize BeamProject
+    let step3_start = std::time::Instant::now();
     let beam_project: BeamProject = serde_json::from_str(&json_data)
         .map_err(|e| format!("Failed to deserialize project.json: {}", e))?;
+    eprintln!("📊 [LOAD_BEAM] Step 3: Deserialize BeamProject took {:.2}ms", step3_start.elapsed().as_secs_f64() * 1000.0);
 
     // 4. Check version compatibility
     if beam_project.version != BEAM_VERSION {
@@ -323,17 +444,23 @@ pub fn load_beam(path: &Path) -> Result<LoadedProject, String> {
     }
 
     // 5. Extract document and audio backend state
+    let step5_start = std::time::Instant::now();
     let document = beam_project.ui_state;
     let mut audio_project = beam_project.audio_backend.project;
     let audio_pool_entries = beam_project.audio_backend.audio_pool_entries;
+    eprintln!("📊 [LOAD_BEAM] Step 5: Extract document and audio state took {:.2}ms", step5_start.elapsed().as_secs_f64() * 1000.0);
 
     // 6. Rebuild AudioGraphs from presets
+    let step6_start = std::time::Instant::now();
     audio_project.rebuild_audio_graphs(DEFAULT_BUFFER_SIZE)
         .map_err(|e| format!("Failed to rebuild audio graphs: {}", e))?;
+    eprintln!("📊 [LOAD_BEAM] Step 6: Rebuild AudioGraphs took {:.2}ms", step6_start.elapsed().as_secs_f64() * 1000.0);
 
     // 7. Extract embedded audio files from ZIP and restore to entries
+    let step7_start = std::time::Instant::now();
     drop(project_file); // Close project.json file handle
     let mut restored_entries = Vec::new();
+    let mut flac_decode_time = 0.0;
 
     for entry in &audio_pool_entries {
         let mut restored_entry = entry.clone();
@@ -357,6 +484,8 @@ pub fn load_beam(path: &Path) -> Result<LoadedProject, String> {
                         // For lossy formats, store the original bytes
                         let embedded_data = if format == "flac" {
                             // Decode FLAC to PCM f32 samples
+                            let flac_decode_start = std::time::Instant::now();
+
                             let cursor = std::io::Cursor::new(&audio_bytes);
                             let mut reader = claxon::FlacReader::new(cursor)
                                 .map_err(|e| format!("Failed to create FLAC reader: {:?}", e))?;
@@ -379,6 +508,8 @@ pub fn load_beam(path: &Path) -> Result<LoadedProject, String> {
                                 pcm_bytes.extend_from_slice(&sample.to_le_bytes());
                             }
 
+                            flac_decode_time += flac_decode_start.elapsed().as_secs_f64() * 1000.0;
+
                             Some(daw_backend::audio::pool::EmbeddedAudioData {
                                 data_base64: base64::encode(&pcm_bytes),
                                 format: "wav".to_string(), // Mark as WAV since it's now PCM
@@ -403,10 +534,16 @@ pub fn load_beam(path: &Path) -> Result<LoadedProject, String> {
 
         restored_entries.push(restored_entry);
     }
+    eprintln!("📊 [LOAD_BEAM] Step 7: Extract embedded audio ({} entries) took {:.2}ms",
+              audio_pool_entries.len(), step7_start.elapsed().as_secs_f64() * 1000.0);
+    if flac_decode_time > 0.0 {
+        eprintln!("📊 [LOAD_BEAM]   - FLAC decoding: {:.2}ms", flac_decode_time);
+    }
 
     // 8. Check for missing external files
     // An entry is missing if it has a relative_path (external reference)
     // but no embedded_data and the file doesn't exist
+    let step8_start = std::time::Instant::now();
     let project_dir = path.parent().unwrap_or_else(|| Path::new("."));
     let missing_files: Vec<MissingFileInfo> = restored_entries
         .iter()
@@ -428,6 +565,9 @@ pub fn load_beam(path: &Path) -> Result<LoadedProject, String> {
             None
         })
         .collect();
+    eprintln!("📊 [LOAD_BEAM] Step 8: Check missing files took {:.2}ms", step8_start.elapsed().as_secs_f64() * 1000.0);
+
+    eprintln!("📊 [LOAD_BEAM] ✅ Total load_beam() time: {:.2}ms", fn_start.elapsed().as_secs_f64() * 1000.0);
 
     Ok(LoadedProject {
         document,
diff --git a/lightningbeam-ui/lightningbeam-editor/src/main.rs b/lightningbeam-ui/lightningbeam-editor/src/main.rs
index a6049a2..a4b76c9 100644
--- a/lightningbeam-ui/lightningbeam-editor/src/main.rs
+++ b/lightningbeam-ui/lightningbeam-editor/src/main.rs
@@ -330,8 +330,12 @@ impl FileOperationsWorker {
     ) {
         use lightningbeam_core::file_io::{save_beam, SaveSettings};
 
+        let save_start = std::time::Instant::now();
+        eprintln!("📊 [SAVE] Starting save operation...");
+
         // Step 1: Serialize audio pool
         let _ = progress_tx.send(FileProgress::SerializingAudioPool);
+        let step1_start = std::time::Instant::now();
 
         let audio_pool_entries = {
             let mut controller = self.audio_controller.lock().unwrap();
@@ -343,8 +347,10 @@ impl FileOperationsWorker {
                 }
             }
         };
+        eprintln!("📊 [SAVE] Step 1: Serialize audio pool took {:.2}ms", step1_start.elapsed().as_secs_f64() * 1000.0);
 
         // Step 2: Get project
+        let step2_start = std::time::Instant::now();
         let mut audio_project = {
             let mut controller = self.audio_controller.lock().unwrap();
             match controller.get_project() {
@@ -355,13 +361,17 @@ impl FileOperationsWorker {
                 }
             }
         };
+        eprintln!("📊 [SAVE] Step 2: Get audio project took {:.2}ms", step2_start.elapsed().as_secs_f64() * 1000.0);
 
         // Step 3: Save to file
         let _ = progress_tx.send(FileProgress::WritingZip);
+        let step3_start = std::time::Instant::now();
 
         let settings = SaveSettings::default();
         match save_beam(&path, &document, &mut audio_project, audio_pool_entries, &settings) {
             Ok(()) => {
+                eprintln!("📊 [SAVE] Step 3: save_beam() took {:.2}ms", step3_start.elapsed().as_secs_f64() * 1000.0);
+                eprintln!("📊 [SAVE] ✅ Total save time: {:.2}ms", save_start.elapsed().as_secs_f64() * 1000.0);
                 println!("✅ Saved to: {}", path.display());
                 let _ = progress_tx.send(FileProgress::Done);
             }
@@ -379,8 +389,12 @@ impl FileOperationsWorker {
     ) {
         use lightningbeam_core::file_io::load_beam;
 
+        let load_start = std::time::Instant::now();
+        eprintln!("📊 [LOAD] Starting load operation...");
+
         // Step 1: Load from file
         let _ = progress_tx.send(FileProgress::LoadingProject);
+        let step1_start = std::time::Instant::now();
 
         let loaded_project = match load_beam(&path) {
             Ok(p) => p,
@@ -389,6 +403,7 @@ impl FileOperationsWorker {
                 return;
             }
         };
+        eprintln!("📊 [LOAD] Step 1: load_beam() took {:.2}ms", step1_start.elapsed().as_secs_f64() * 1000.0);
 
         // Check for missing files
         if !loaded_project.missing_files.is_empty() {
@@ -398,6 +413,8 @@ impl FileOperationsWorker {
             }
         }
 
+        eprintln!("📊 [LOAD] ✅ Total load time: {:.2}ms", load_start.elapsed().as_secs_f64() * 1000.0);
+
         // Send the loaded project back to UI thread for processing
         let _ = progress_tx.send(FileProgress::Complete(Ok(loaded_project)));
     }
@@ -455,6 +472,10 @@ struct EditorApp {
     /// Prevents repeated backend queries for the same MIDI clip
     /// Format: (timestamp, note_number, is_note_on)
     midi_event_cache: HashMap<u32, Vec<(f64, u8, bool)>>,
+    /// Cache for audio waveform data (keyed by audio_pool_index)
+    /// Prevents repeated backend queries for the same audio file
+    /// Format: Vec of WaveformPeak (min/max pairs)
+    waveform_cache: HashMap<usize, Vec<daw_backend::WaveformPeak>>,
     /// Current file path (None if not yet saved)
     current_file_path: Option<std::path::PathBuf>,
 
@@ -578,6 +599,7 @@ impl EditorApp {
             paint_bucket_gap_tolerance: 5.0, // Default gap tolerance
             polygon_sides: 5,                // Default to pentagon
             midi_event_cache: HashMap::new(), // Initialize empty MIDI event cache
+            waveform_cache: HashMap::new(), // Initialize empty waveform cache
             current_file_path: None, // No file loaded initially
             file_command_tx,
             file_operation: None, // No file operation in progress initially
@@ -590,48 +612,71 @@ impl EditorApp {
     /// - After loading a document from file
     /// - After creating a new document with pre-existing MIDI layers
     ///
-    /// For each MIDI audio layer:
-    /// 1. Creates a daw-backend MIDI track
-    /// 2. Loads the default instrument
+    /// For each audio layer (MIDI or Sampled):
+    /// 1. Creates a daw-backend track (MIDI or Audio)
+    /// 2. For MIDI: Loads the default instrument
     /// 3. Stores the bidirectional mapping
     /// 4. Syncs any existing clips on the layer
-    fn sync_midi_layers_to_backend(&mut self) {
+    fn sync_audio_layers_to_backend(&mut self) {
         use lightningbeam_core::layer::{AnyLayer, AudioLayerType};
 
         // Iterate through all layers in the document
         for layer in &self.action_executor.document().root.children {
-            // Only process Audio layers with MIDI type
+            // Only process Audio layers
             if let AnyLayer::Audio(audio_layer) = layer {
-                if audio_layer.audio_layer_type == AudioLayerType::Midi {
-                    let layer_id = audio_layer.layer.id;
-                    let layer_name = &audio_layer.layer.name;
+                let layer_id = audio_layer.layer.id;
+                let layer_name = &audio_layer.layer.name;
 
-                    // Skip if already mapped (shouldn't happen, but be defensive)
-                    if self.layer_to_track_map.contains_key(&layer_id) {
-                        continue;
-                    }
+                // Skip if already mapped (shouldn't happen, but be defensive)
+                if self.layer_to_track_map.contains_key(&layer_id) {
+                    continue;
+                }
 
-                    // Create daw-backend MIDI track
-                    if let Some(ref controller_arc) = self.audio_controller {
-                    let mut controller = controller_arc.lock().unwrap();
-                        match controller.create_midi_track_sync(layer_name.clone()) {
-                            Ok(track_id) => {
-                                // Store bidirectional mapping
-                                self.layer_to_track_map.insert(layer_id, track_id);
-                                self.track_to_layer_map.insert(track_id, layer_id);
+                // Handle both MIDI and Sampled audio tracks
+                match audio_layer.audio_layer_type {
+                    AudioLayerType::Midi => {
+                        // Create daw-backend MIDI track
+                        if let Some(ref controller_arc) = self.audio_controller {
+                            let mut controller = controller_arc.lock().unwrap();
+                            match controller.create_midi_track_sync(layer_name.clone()) {
+                                Ok(track_id) => {
+                                    // Store bidirectional mapping
+                                    self.layer_to_track_map.insert(layer_id, track_id);
+                                    self.track_to_layer_map.insert(track_id, layer_id);
 
-                                // Load default instrument
-                                if let Err(e) = default_instrument::load_default_instrument(&mut *controller, track_id) {
-                                    eprintln!("⚠️  Failed to load default instrument for {}: {}", layer_name, e);
-                                } else {
-                                    println!("✅ Synced MIDI layer '{}' to backend (TrackId: {})", layer_name, track_id);
+                                    // Load default instrument
+                                    if let Err(e) = default_instrument::load_default_instrument(&mut *controller, track_id) {
+                                        eprintln!("⚠️  Failed to load default instrument for {}: {}", layer_name, e);
+                                    } else {
+                                        println!("✅ Synced MIDI layer '{}' to backend (TrackId: {})", layer_name, track_id);
+                                    }
+
+                                    // TODO: Sync any existing clips on this layer to the backend
+                                    // This will be implemented when we add clip synchronization
+                                }
+                                Err(e) => {
+                                    eprintln!("⚠️  Failed to create daw-backend track for MIDI layer '{}': {}", layer_name, e);
                                 }
-
-                                // TODO: Sync any existing clips on this layer to the backend
-                                // This will be implemented when we add clip synchronization
                             }
-                            Err(e) => {
-                                eprintln!("⚠️  Failed to create daw-backend track for MIDI layer '{}': {}", layer_name, e);
+                        }
+                    }
+                    AudioLayerType::Sampled => {
+                        // Create daw-backend Audio track
+                        if let Some(ref controller_arc) = self.audio_controller {
+                            let mut controller = controller_arc.lock().unwrap();
+                            match controller.create_audio_track_sync(layer_name.clone()) {
+                                Ok(track_id) => {
+                                    // Store bidirectional mapping
+                                    self.layer_to_track_map.insert(layer_id, track_id);
+                                    self.track_to_layer_map.insert(track_id, layer_id);
+                                    println!("✅ Synced Audio layer '{}' to backend (TrackId: {})", layer_name, track_id);
+
+                                    // TODO: Sync any existing clips on this layer to the backend
+                                    // This will be implemented when we add clip synchronization
+                                }
+                                Err(e) => {
+                                    eprintln!("⚠️  Failed to create daw-backend audio track for '{}': {}", layer_name, e);
+                                }
                             }
                         }
                     }
@@ -640,6 +685,34 @@ impl EditorApp {
         }
     }
 
+    /// Fetch waveform data from backend for a specific audio pool index
+    /// Returns cached data if available, otherwise queries backend
+    fn fetch_waveform(&mut self, pool_index: usize) -> Option<Vec<daw_backend::WaveformPeak>> {
+        // Check if already cached
+        if let Some(waveform) = self.waveform_cache.get(&pool_index) {
+            return Some(waveform.clone());
+        }
+
+        // Fetch from backend
+        // Request 20,000 peaks for high-detail waveform visualization
+        // For a 200s file, this gives ~100 peaks/second, providing smooth visualization at all zoom levels
+        if let Some(ref controller_arc) = self.audio_controller {
+            let mut controller = controller_arc.lock().unwrap();
+            match controller.get_pool_waveform(pool_index, 20000) {
+                Ok(waveform) => {
+                    self.waveform_cache.insert(pool_index, waveform.clone());
+                    Some(waveform)
+                }
+                Err(e) => {
+                    eprintln!("⚠️  Failed to fetch waveform for pool index {}: {}", pool_index, e);
+                    None
+                }
+            }
+        } else {
+            None
+        }
+    }
+
     fn switch_layout(&mut self, index: usize) {
         self.current_layout_index = index;
         self.current_layout = self.layouts[index].layout.clone();
@@ -969,8 +1042,37 @@ impl EditorApp {
                 // TODO: Implement add video layer
             }
             MenuAction::AddAudioTrack => {
-                println!("Menu: Add Audio Track");
-                // TODO: Implement add audio track
+                // Create a new sampled audio layer with a default name
+                let layer_count = self.action_executor.document().root.children.len();
+                let layer_name = format!("Audio Track {}", layer_count + 1);
+
+                // Create audio layer in document
+                let audio_layer = AudioLayer::new_sampled(layer_name.clone());
+                let action = lightningbeam_core::actions::AddLayerAction::new(AnyLayer::Audio(audio_layer));
+                self.action_executor.execute(Box::new(action));
+
+                // Get the newly created layer ID
+                if let Some(last_layer) = self.action_executor.document().root.children.last() {
+                    let layer_id = last_layer.id();
+                    self.active_layer_id = Some(layer_id);
+
+                    // Create corresponding daw-backend audio track
+                    if let Some(ref controller_arc) = self.audio_controller {
+                        let mut controller = controller_arc.lock().unwrap();
+                        match controller.create_audio_track_sync(layer_name.clone()) {
+                            Ok(track_id) => {
+                                // Store bidirectional mapping
+                                self.layer_to_track_map.insert(layer_id, track_id);
+                                self.track_to_layer_map.insert(track_id, layer_id);
+                                println!("✅ Created {} (backend TrackId: {})", layer_name, track_id);
+                            }
+                            Err(e) => {
+                                eprintln!("⚠️  Failed to create daw-backend audio track for {}: {}", layer_name, e);
+                                eprintln!("   Layer created but will be silent until backend track is available");
+                            }
+                        }
+                    }
+                }
             }
             MenuAction::AddMidiTrack => {
                 // Create a new MIDI audio layer with a default name
@@ -1270,6 +1372,9 @@ impl EditorApp {
     fn apply_loaded_project(&mut self, loaded_project: lightningbeam_core::file_io::LoadedProject, path: std::path::PathBuf) {
         use lightningbeam_core::action::ActionExecutor;
 
+        let apply_start = std::time::Instant::now();
+        eprintln!("📊 [APPLY] Starting apply_loaded_project() on UI thread...");
+
         // Check for missing files
         if !loaded_project.missing_files.is_empty() {
             eprintln!("⚠️ {} missing files", loaded_project.missing_files.len());
@@ -1280,33 +1385,78 @@ impl EditorApp {
         }
 
         // Replace document
+        let step1_start = std::time::Instant::now();
         self.action_executor = ActionExecutor::new(loaded_project.document);
+        eprintln!("📊 [APPLY] Step 1: Replace document took {:.2}ms", step1_start.elapsed().as_secs_f64() * 1000.0);
 
         // Restore UI layout from loaded document
+        let step2_start = std::time::Instant::now();
         self.restore_layout_from_document();
+        eprintln!("📊 [APPLY] Step 2: Restore UI layout took {:.2}ms", step2_start.elapsed().as_secs_f64() * 1000.0);
 
         // Set project in audio engine via query
+        let step3_start = std::time::Instant::now();
         if let Some(ref controller_arc) = self.audio_controller {
             let mut controller = controller_arc.lock().unwrap();
             if let Err(e) = controller.set_project(loaded_project.audio_project) {
                 eprintln!("❌ Failed to set project: {}", e);
                 return;
             }
+            eprintln!("📊 [APPLY] Step 3: Set audio project took {:.2}ms", step3_start.elapsed().as_secs_f64() * 1000.0);
 
-            // Load audio pool
-            if let Err(e) = controller.load_audio_pool(
-                loaded_project.audio_pool_entries,
-                &path,
-            ) {
-                eprintln!("❌ Failed to load audio pool: {}", e);
-                return;
-            }
+            // Load audio pool asynchronously to avoid blocking UI
+            let step4_start = std::time::Instant::now();
+            let controller_clone = controller_arc.clone();
+            let path_clone = path.clone();
+            let audio_pool_entries = loaded_project.audio_pool_entries;
+
+            std::thread::spawn(move || {
+                eprintln!("📊 [APPLY] Step 4: Starting async audio pool load...");
+                let load_start = std::time::Instant::now();
+                let mut controller = controller_clone.lock().unwrap();
+                if let Err(e) = controller.load_audio_pool(audio_pool_entries, &path_clone) {
+                    eprintln!("❌ Failed to load audio pool: {}", e);
+                } else {
+                    eprintln!("📊 [APPLY] Step 4: Async audio pool load completed in {:.2}ms", load_start.elapsed().as_secs_f64() * 1000.0);
+                }
+            });
+            eprintln!("📊 [APPLY] Step 4: Spawned async audio pool load in {:.2}ms", step4_start.elapsed().as_secs_f64() * 1000.0);
         }
 
         // Reset state
+        let step5_start = std::time::Instant::now();
         self.layer_to_track_map.clear();
         self.track_to_layer_map.clear();
-        self.sync_midi_layers_to_backend();
+        eprintln!("📊 [APPLY] Step 5: Clear track maps took {:.2}ms", step5_start.elapsed().as_secs_f64() * 1000.0);
+
+        // Sync audio layers (MIDI and Sampled)
+        let step6_start = std::time::Instant::now();
+        self.sync_audio_layers_to_backend();
+        eprintln!("📊 [APPLY] Step 6: Sync audio layers took {:.2}ms", step6_start.elapsed().as_secs_f64() * 1000.0);
+
+        // Fetch waveforms for all audio clips in the loaded project
+        let step7_start = std::time::Instant::now();
+        // Collect pool indices first to avoid borrowing issues
+        let pool_indices: Vec<usize> = self.action_executor.document()
+            .audio_clips.values()
+            .filter_map(|clip| {
+                if let lightningbeam_core::clip::AudioClipType::Sampled { audio_pool_index } = &clip.clip_type {
+                    Some(*audio_pool_index)
+                } else {
+                    None
+                }
+            })
+            .collect();
+
+        let mut waveforms_fetched = 0;
+        for pool_index in pool_indices {
+            if self.fetch_waveform(pool_index).is_some() {
+                waveforms_fetched += 1;
+            }
+        }
+        eprintln!("📊 [APPLY] Step 7: Fetched {} waveforms in {:.2}ms", waveforms_fetched, step7_start.elapsed().as_secs_f64() * 1000.0);
+
+        // Reset playback state
         self.playback_time = 0.0;
         self.is_playing = false;
         self.current_file_path = Some(path.clone());
@@ -1316,6 +1466,7 @@ impl EditorApp {
             self.active_layer_id = Some(first.id());
         }
 
+        eprintln!("📊 [APPLY] ✅ Total apply_loaded_project() time: {:.2}ms", apply_start.elapsed().as_secs_f64() * 1000.0);
         println!("✅ Loaded from: {}", path.display());
     }
 
@@ -1376,23 +1527,31 @@ impl EditorApp {
 
                 // Add to audio engine pool if available
                 if let Some(ref controller_arc) = self.audio_controller {
-                    let mut controller = controller_arc.lock().unwrap();
-                    // Send audio data to the engine
-                    let path_str = path.to_string_lossy().to_string();
-                    controller.add_audio_file(
-                        path_str.clone(),
-                        audio_file.data,
-                        channels,
-                        sample_rate,
-                    );
+                    let pool_index = {
+                        let mut controller = controller_arc.lock().unwrap();
+                        // Send audio data to the engine
+                        let path_str = path.to_string_lossy().to_string();
+                        controller.add_audio_file(
+                            path_str.clone(),
+                            audio_file.data,
+                            channels,
+                            sample_rate,
+                        );
 
-                    // For now, use a placeholder pool index (the engine will assign the real one)
-                    // In a full implementation, we'd wait for the AudioFileAdded event
-                    let pool_index = self.action_executor.document().audio_clips.len();
+                        // For now, use a placeholder pool index (the engine will assign the real one)
+                        // In a full implementation, we'd wait for the AudioFileAdded event
+                        self.action_executor.document().audio_clips.len()
+                    }; // Controller lock is dropped here
 
                     // Create audio clip in document
                     let clip = AudioClip::new_sampled(&name, pool_index, duration);
                     let clip_id = self.action_executor.document_mut().add_audio_clip(clip);
+
+                    // Fetch waveform from backend and cache it for rendering
+                    if let Some(waveform) = self.fetch_waveform(pool_index) {
+                        println!("✅ Cached waveform with {} peaks", waveform.len());
+                    }
+
                     println!("Imported audio '{}' ({:.1}s, {}ch, {}Hz) - ID: {}",
                         name, duration, channels, sample_rate, clip_id);
                 } else {
@@ -1504,6 +1663,29 @@ impl eframe::App for EditorApp {
             }
         }
 
+        // Fetch missing waveforms on-demand (for lazy loading after project load)
+        // Collect pool indices that need waveforms
+        let missing_waveforms: Vec<usize> = self.action_executor.document()
+            .audio_clips.values()
+            .filter_map(|clip| {
+                if let lightningbeam_core::clip::AudioClipType::Sampled { audio_pool_index } = &clip.clip_type {
+                    // Check if not already cached
+                    if !self.waveform_cache.contains_key(audio_pool_index) {
+                        Some(*audio_pool_index)
+                    } else {
+                        None
+                    }
+                } else {
+                    None
+                }
+            })
+            .collect();
+
+        // Fetch missing waveforms
+        for pool_index in missing_waveforms {
+            self.fetch_waveform(pool_index);
+        }
+
         // Handle file operation progress
         if let Some(ref mut operation) = self.file_operation {
             // Set wait cursor
@@ -1675,6 +1857,7 @@ impl eframe::App for EditorApp {
                 polygon_sides: &mut self.polygon_sides,
                 layer_to_track_map: &self.layer_to_track_map,
                 midi_event_cache: &self.midi_event_cache,
+                waveform_cache: &self.waveform_cache,
             };
 
             render_layout_node(
@@ -1843,6 +2026,8 @@ struct RenderContext<'a> {
     layer_to_track_map: &'a std::collections::HashMap<Uuid, daw_backend::TrackId>,
     /// Cache of MIDI events for rendering (keyed by backend midi_clip_id)
     midi_event_cache: &'a HashMap<u32, Vec<(f64, u8, bool)>>,
+    /// Cache of waveform data for rendering (keyed by audio_pool_index)
+    waveform_cache: &'a HashMap<usize, Vec<daw_backend::WaveformPeak>>,
 }
 
 /// Recursively render a layout node with drag support
@@ -2314,6 +2499,7 @@ fn render_pane(
                 paint_bucket_gap_tolerance: ctx.paint_bucket_gap_tolerance,
                 polygon_sides: ctx.polygon_sides,
                 midi_event_cache: ctx.midi_event_cache,
+                waveform_cache: ctx.waveform_cache,
             };
             pane_instance.render_header(&mut header_ui, &mut shared);
         }
@@ -2368,6 +2554,7 @@ fn render_pane(
                 paint_bucket_gap_tolerance: ctx.paint_bucket_gap_tolerance,
                 polygon_sides: ctx.polygon_sides,
                 midi_event_cache: ctx.midi_event_cache,
+                waveform_cache: ctx.waveform_cache,
             };
 
             // Render pane content (header was already rendered above)
diff --git a/lightningbeam-ui/lightningbeam-editor/src/panes/mod.rs b/lightningbeam-ui/lightningbeam-editor/src/panes/mod.rs
index 95e8142..3d9e5c5 100644
--- a/lightningbeam-ui/lightningbeam-editor/src/panes/mod.rs
+++ b/lightningbeam-ui/lightningbeam-editor/src/panes/mod.rs
@@ -127,6 +127,8 @@ pub struct SharedPaneState<'a> {
     pub polygon_sides: &'a mut u32,
     /// Cache of MIDI events for rendering (keyed by backend midi_clip_id)
     pub midi_event_cache: &'a std::collections::HashMap<u32, Vec<(f64, u8, bool)>>,
+    /// Cache of waveform data for rendering (keyed by audio_pool_index)
+    pub waveform_cache: &'a std::collections::HashMap<usize, Vec<daw_backend::WaveformPeak>>,
 }
 
 /// Trait for pane rendering
diff --git a/lightningbeam-ui/lightningbeam-editor/src/panes/timeline.rs b/lightningbeam-ui/lightningbeam-editor/src/panes/timeline.rs
index a4581a1..2f9929d 100644
--- a/lightningbeam-ui/lightningbeam-editor/src/panes/timeline.rs
+++ b/lightningbeam-ui/lightningbeam-editor/src/panes/timeline.rs
@@ -14,7 +14,7 @@ use super::{DragClipType, NodePath, PaneRenderer, SharedPaneState};
 const RULER_HEIGHT: f32 = 30.0;
 const LAYER_HEIGHT: f32 = 60.0;
 const LAYER_HEADER_WIDTH: f32 = 200.0;
-const MIN_PIXELS_PER_SECOND: f32 = 20.0;
+const MIN_PIXELS_PER_SECOND: f32 = 1.0;  // Allow zooming out to see 10+ minutes
 const MAX_PIXELS_PER_SECOND: f32 = 500.0;
 const EDGE_DETECTION_PIXELS: f32 = 8.0; // Distance from edge to detect trim handles
 
@@ -456,6 +456,135 @@ impl TimelinePane {
         }
     }
 
+    /// Render waveform visualization for audio clips on timeline
+    /// Uses peak-based rendering: each waveform sample has a fixed pixel width that scales with zoom
+    #[allow(clippy::too_many_arguments)]
+    fn render_audio_waveform(
+        painter: &egui::Painter,
+        clip_rect: egui::Rect,
+        clip_start_x: f32, // Absolute screen x where clip starts (can be offscreen)
+        clip_bg_color: egui::Color32, // Background color of the clip
+        waveform: &[daw_backend::WaveformPeak],
+        clip_duration: f64,
+        pixels_per_second: f32,
+        trim_start: f64,
+        theme: &crate::theme::Theme,
+        ctx: &egui::Context,
+    ) {
+        if waveform.is_empty() {
+            return;
+        }
+
+        let clip_height = clip_rect.height();
+        let center_y = clip_rect.center().y;
+
+        // Calculate waveform color: lighten the clip background color
+        // Blend clip background with white (70% white + 30% clip color) for subtle tint
+        // Use full opacity to prevent overlapping lines from blending lighter when zoomed out
+        let r = ((255.0 * 0.7) + (clip_bg_color.r() as f32 * 0.3)) as u8;
+        let g = ((255.0 * 0.7) + (clip_bg_color.g() as f32 * 0.3)) as u8;
+        let b = ((255.0 * 0.7) + (clip_bg_color.b() as f32 * 0.3)) as u8;
+        let waveform_color = egui::Color32::from_rgb(r, g, b);
+
+        // Calculate how wide each peak should be at current zoom (mirrors JavaScript)
+        // fullSourceWidth = sourceDuration * pixelsPerSecond
+        // pixelsPerPeak = fullSourceWidth / waveformData.length
+        let full_source_width = clip_duration * pixels_per_second as f64;
+        let pixels_per_peak = full_source_width / waveform.len() as f64;
+
+        // Calculate which peak corresponds to the clip's offset (trimmed left edge)
+        let offset_peak_index = ((trim_start / clip_duration) * waveform.len() as f64).floor() as usize;
+        let offset_peak_index = offset_peak_index.min(waveform.len().saturating_sub(1));
+
+        // Calculate visible peak range
+        // firstVisiblePeak = max(offsetPeakIndex, floor((visibleStart - startX) / pixelsPerPeak) + offsetPeakIndex)
+        let visible_start = clip_rect.min.x;
+        let visible_end = clip_rect.max.x;
+
+        let first_visible_peak_from_viewport = if pixels_per_peak > 0.0 {
+            (((visible_start - clip_start_x) as f64 / pixels_per_peak).floor() as isize + offset_peak_index as isize).max(0)
+        } else {
+            offset_peak_index as isize
+        };
+        let first_visible_peak = (first_visible_peak_from_viewport as usize).max(offset_peak_index);
+
+        let last_visible_peak_from_viewport = if pixels_per_peak > 0.0 {
+            ((visible_end - clip_start_x) as f64 / pixels_per_peak).ceil() as isize + offset_peak_index as isize
+        } else {
+            offset_peak_index as isize
+        };
+        let last_visible_peak = (last_visible_peak_from_viewport as usize)
+            .min(waveform.len().saturating_sub(1));
+
+        if first_visible_peak > last_visible_peak || first_visible_peak >= waveform.len() {
+            return;
+        }
+
+        println!("\n🎵 WAVEFORM RENDER:");
+        println!("  Waveform total peaks: {}", waveform.len());
+        println!("  Clip duration: {:.2}s", clip_duration);
+        println!("  Pixels per second: {}", pixels_per_second);
+        println!("  Pixels per peak: {:.4}", pixels_per_peak);
+        println!("  Trim start: {:.2}s", trim_start);
+        println!("  Offset peak index: {}", offset_peak_index);
+        println!("  Clip start X: {:.1}", clip_start_x);
+        println!("  Clip rect: x=[{:.1}, {:.1}], y=[{:.1}, {:.1}]",
+                 clip_rect.min.x, clip_rect.max.x, clip_rect.min.y, clip_rect.max.y);
+        println!("  Visible start: {:.1}, end: {:.1}", visible_start, visible_end);
+        println!("  First visible peak: {} (time: {:.2}s)",
+                 first_visible_peak, first_visible_peak as f64 * clip_duration / waveform.len() as f64);
+        println!("  Last visible peak: {} (time: {:.2}s)",
+                 last_visible_peak, last_visible_peak as f64 * clip_duration / waveform.len() as f64);
+        println!("  Peak range size: {}", last_visible_peak - first_visible_peak + 1);
+
+        // Draw waveform as vertical lines from min to max
+        // Line width scales with zoom to avoid gaps between peaks
+        let line_width = if pixels_per_peak > 1.0 {
+            pixels_per_peak.ceil() as f32
+        } else {
+            1.0
+        };
+
+        let mut peaks_drawn = 0;
+        let mut lines = Vec::new();
+
+        for i in first_visible_peak..=last_visible_peak {
+            if i >= waveform.len() {
+                break;
+            }
+
+            let peak_x = clip_start_x + ((i as isize - offset_peak_index as isize) as f64 * pixels_per_peak) as f32;
+            let peak = &waveform[i];
+
+            // Calculate Y positions for min and max
+            let max_y = center_y + (peak.max * clip_height * 0.45);
+            let min_y = center_y + (peak.min * clip_height * 0.45);
+
+            if peaks_drawn < 3 {
+                println!("  PEAK[{}]: x={:.1}, min={:.3} (y={:.1}), max={:.3} (y={:.1})",
+                         i, peak_x, peak.min, min_y, peak.max, max_y);
+            }
+
+            // Draw vertical line from min to max
+            lines.push((
+                egui::pos2(peak_x, max_y),
+                egui::pos2(peak_x, min_y),
+            ));
+
+            peaks_drawn += 1;
+        }
+
+        println!("  Peaks drawn: {}, line width: {:.1}px", peaks_drawn, line_width);
+
+        // Draw all lines with clipping
+        for (start, end) in lines {
+            painter.with_clip_rect(clip_rect).line_segment(
+                [start, end],
+                egui::Stroke::new(line_width, waveform_color),
+            );
+        }
+    }
+
     /// Render layer header column (left side with track names and controls)
     fn render_layer_headers(
         &mut self,
@@ -514,9 +643,14 @@ impl TimelinePane {
             let layer_data = layer.layer();
             let layer_name = &layer_data.name;
             let (layer_type, type_color) = match layer {
-                lightningbeam_core::layer::AnyLayer::Vector(_) => ("Vector", egui::Color32::from_rgb(100, 150, 255)), // Blue
-                lightningbeam_core::layer::AnyLayer::Audio(_) => ("Audio", egui::Color32::from_rgb(100, 255, 150)), // Green
-                lightningbeam_core::layer::AnyLayer::Video(_) => ("Video", egui::Color32::from_rgb(255, 150, 100)), // Orange
+                lightningbeam_core::layer::AnyLayer::Vector(_) => ("Vector", egui::Color32::from_rgb(255, 180, 100)), // Orange
+                lightningbeam_core::layer::AnyLayer::Audio(audio_layer) => {
+                    match audio_layer.audio_layer_type {
+                        lightningbeam_core::layer::AudioLayerType::Midi => ("MIDI", egui::Color32::from_rgb(100, 255, 150)), // Green
+                        lightningbeam_core::layer::AudioLayerType::Sampled => ("Audio", egui::Color32::from_rgb(100, 180, 255)), // Blue
+                    }
+                }
+                lightningbeam_core::layer::AnyLayer::Video(_) => ("Video", egui::Color32::from_rgb(255, 150, 100)), // Orange/Red
             };
 
             // Color indicator bar on the left edge
@@ -735,6 +869,7 @@ impl TimelinePane {
         active_layer_id: &Option<uuid::Uuid>,
         selection: &lightningbeam_core::selection::Selection,
         midi_event_cache: &std::collections::HashMap<u32, Vec<(f64, u8, bool)>>,
+        waveform_cache: &std::collections::HashMap<usize, Vec<daw_backend::WaveformPeak>>,
     ) {
         let painter = ui.painter();
 
@@ -875,16 +1010,24 @@ impl TimelinePane {
                         // Choose color based on layer type
                         let (clip_color, bright_color) = match layer {
                             lightningbeam_core::layer::AnyLayer::Vector(_) => (
-                                egui::Color32::from_rgb(100, 150, 255), // Blue
-                                egui::Color32::from_rgb(150, 200, 255), // Bright blue
-                            ),
-                            lightningbeam_core::layer::AnyLayer::Audio(_) => (
-                                egui::Color32::from_rgb(100, 255, 150), // Green
-                                egui::Color32::from_rgb(150, 255, 200), // Bright green
+                                egui::Color32::from_rgb(220, 150, 80), // Orange
+                                egui::Color32::from_rgb(255, 210, 150), // Bright orange
                             ),
+                            lightningbeam_core::layer::AnyLayer::Audio(audio_layer) => {
+                                match audio_layer.audio_layer_type {
+                                    lightningbeam_core::layer::AudioLayerType::Midi => (
+                                        egui::Color32::from_rgb(100, 200, 150), // Green
+                                        egui::Color32::from_rgb(150, 255, 200), // Bright green
+                                    ),
+                                    lightningbeam_core::layer::AudioLayerType::Sampled => (
+                                        egui::Color32::from_rgb(80, 150, 220), // Blue
+                                        egui::Color32::from_rgb(150, 210, 255), // Bright blue
+                                    ),
+                                }
+                            }
                             lightningbeam_core::layer::AnyLayer::Video(_) => (
-                                egui::Color32::from_rgb(255, 150, 100), // Orange
-                                egui::Color32::from_rgb(255, 200, 150), // Bright orange
+                                egui::Color32::from_rgb(255, 150, 100), // Orange/Red
+                                egui::Color32::from_rgb(255, 200, 150), // Bright orange/red
                             ),
                         };
 
@@ -900,24 +1043,47 @@ impl TimelinePane {
                             clip_color,
                         );
 
-                        // MIDI VISUALIZATION: Draw piano roll overlay for MIDI clips
+                        // AUDIO VISUALIZATION: Draw piano roll or waveform overlay
                         if let lightningbeam_core::layer::AnyLayer::Audio(_) = layer {
                             if let Some(clip) = document.get_audio_clip(&clip_instance.clip_id) {
-                                if let lightningbeam_core::clip::AudioClipType::Midi { midi_clip_id } = &clip.clip_type {
-                                    if let Some(events) = midi_event_cache.get(midi_clip_id) {
-                                        Self::render_midi_piano_roll(
-                                            painter,
-                                            clip_rect,
-                                            rect.min.x, // Pass timeline panel left edge for proper positioning
-                                            events,
-                                            clip_instance.trim_start,
-                                            instance_duration,
-                                            instance_start,
-                                            self.viewport_start_time,
-                                            self.pixels_per_second,
-                                            theme,
-                                            ui.ctx(),
-                                        );
+                                match &clip.clip_type {
+                                    // MIDI: Draw piano roll
+                                    lightningbeam_core::clip::AudioClipType::Midi { midi_clip_id } => {
+                                        if let Some(events) = midi_event_cache.get(midi_clip_id) {
+                                            Self::render_midi_piano_roll(
+                                                painter,
+                                                clip_rect,
+                                                rect.min.x, // Pass timeline panel left edge for proper positioning
+                                                events,
+                                                clip_instance.trim_start,
+                                                instance_duration,
+                                                instance_start,
+                                                self.viewport_start_time,
+                                                self.pixels_per_second,
+                                                theme,
+                                                ui.ctx(),
+                                            );
+                                        }
+                                    }
+                                    // Sampled Audio: Draw waveform
+                                    lightningbeam_core::clip::AudioClipType::Sampled { audio_pool_index } => {
+                                        if let Some(waveform) = waveform_cache.get(audio_pool_index) {
+                                            // Calculate absolute screen x where clip starts (can be offscreen)
+                                            let clip_start_x = rect.min.x + start_x;
+
+                                            Self::render_audio_waveform(
+                                                painter,
+                                                clip_rect,
+                                                clip_start_x,
+                                                clip_color, // Pass clip background color for tinting
+                                                waveform,
+                                                clip.duration,
+                                                self.pixels_per_second,
+                                                clip_instance.trim_start,
+                                                theme,
+                                                ui.ctx(),
+                                            );
+                                        }
                                     }
                                 }
                             }
@@ -1673,7 +1839,7 @@ impl PaneRenderer for TimelinePane {
 
         // Render layer rows with clipping
         ui.set_clip_rect(content_rect.intersect(original_clip_rect));
-        self.render_layers(ui, content_rect, shared.theme, document, shared.active_layer_id, shared.selection, shared.midi_event_cache);
+        self.render_layers(ui, content_rect, shared.theme, document, shared.active_layer_id, shared.selection, shared.midi_event_cache, shared.waveform_cache);
 
         // Render playhead on top (clip to timeline area)
         ui.set_clip_rect(timeline_rect.intersect(original_clip_rect));