5 files changed, 31 insertions, 8 deletions
diff --git a/src/audio/audio.cc b/src/audio/audio.cc
index 67345cf..74536e5 100644
--- a/src/audio/audio.cc
+++ b/src/audio/audio.cc
@@ -172,6 +172,12 @@ float audio_get_playback_time() {
          (RING_BUFFER_SAMPLE_RATE * RING_BUFFER_CHANNELS);
 }
 
+float audio_get_render_time() {
+  const int64_t total_samples = g_ring_buffer.get_total_written();
+  return (float)total_samples /
+         (RING_BUFFER_SAMPLE_RATE * RING_BUFFER_CHANNELS);
+}
+
 float audio_get_realtime_peak() {
   if (g_audio_backend == nullptr) {
     return 0.0f;
diff --git a/src/audio/audio.h b/src/audio/audio.h
index 14fe615..e063a57 100644
--- a/src/audio/audio.h
+++ b/src/audio/audio.h
@@ -27,8 +27,14 @@ void audio_start(); // Starts the audio device callback
 void audio_render_ahead(float music_time, float dt);
 
 // Get current playback time (in seconds) based on samples consumed
+// This is the ring buffer READ position (what's being played NOW)
 float audio_get_playback_time();
 
+// Get current render time (in seconds) based on samples written
+// This is the ring buffer WRITE position (where we're currently rendering)
+// Use this for calculating sample-accurate trigger offsets
+float audio_get_render_time();
+
 // Get peak amplitude of samples currently being played (real-time sync)
 // Returns: Peak amplitude in range [0.0, 1.0+]
 // Use this for visual effects to ensure audio-visual synchronization
diff --git a/src/audio/ring_buffer.cc b/src/audio/ring_buffer.cc
index a7e5d9e..7cedb56 100644
--- a/src/audio/ring_buffer.cc
+++ b/src/audio/ring_buffer.cc
@@ -9,7 +9,7 @@
 
 AudioRingBuffer::AudioRingBuffer()
     : capacity_(RING_BUFFER_CAPACITY_SAMPLES), write_pos_(0), read_pos_(0),
-      total_read_(0) {
+      total_read_(0), total_written_(0) {
   memset(buffer_, 0, sizeof(buffer_));
 }
 
@@ -81,6 +81,9 @@ int AudioRingBuffer::write(const float* samples, int count) {
     write_pos_.store(remainder, std::memory_order_release);
   }
 
+  // Track total samples written for render timing
+  total_written_.fetch_add(to_write, std::memory_order_release);
+
   return to_write;
 }
 
diff --git a/src/audio/ring_buffer.h b/src/audio/ring_buffer.h
index b19c1ea..324447a 100644
--- a/src/audio/ring_buffer.h
+++ b/src/audio/ring_buffer.h
@@ -42,6 +42,11 @@ class AudioRingBuffer {
     return total_read_.load(std::memory_order_acquire);
   }
 
+  // Get total samples written (for render timing)
+  int64_t get_total_written() const {
+    return total_written_.load(std::memory_order_acquire);
+  }
+
   // Clear buffer (for seeking)
   void clear();
 
@@ -49,7 +54,8 @@ class AudioRingBuffer {
   float buffer_[RING_BUFFER_CAPACITY_SAMPLES];
   int capacity_; // Total capacity in samples
 
-  std::atomic<int> write_pos_;      // Write position (0 to capacity-1)
-  std::atomic<int> read_pos_;       // Read position (0 to capacity-1)
-  std::atomic<int64_t> total_read_; // Total samples read (for playback time)
+  std::atomic<int> write_pos_;        // Write position (0 to capacity-1)
+  std::atomic<int> read_pos_;         // Read position (0 to capacity-1)
+  std::atomic<int64_t> total_read_;   // Total samples read (for playback time)
+  std::atomic<int64_t> total_written_; // Total samples written (for render timing)
 };
diff --git a/src/audio/tracker.cc b/src/audio/tracker.cc
index 93a1c49..1cccc57 100644
--- a/src/audio/tracker.cc
+++ b/src/audio/tracker.cc
@@ -239,8 +239,9 @@ void tracker_update(float music_time_sec) {
   }
 
   // Step 2: Update all active patterns and trigger individual events
-  // Get current audio playback position for sample-accurate timing
-  const float current_playback_time = audio_get_playback_time();
+  // Get current audio RENDER position (write position) for sample-accurate timing
+  // This is where we're currently writing to the ring buffer (~400ms ahead of playback)
+  const float current_render_time = audio_get_render_time();
   const float SAMPLE_RATE = 32000.0f; // Audio sample rate
 
   for (int i = 0; i < MAX_SPECTROGRAMS; ++i) {
@@ -265,8 +266,9 @@ void tracker_update(float music_time_sec) {
       const float event_trigger_time = active.start_music_time +
                                        (event.unit_time * unit_duration_sec);
 
-      // Calculate sample-accurate offset from current playback position
-      const float time_delta = event_trigger_time - current_playback_time;
+      // Calculate sample-accurate offset from current RENDER position (write pos)
+      // This is where we're currently writing to the buffer, not where playback is
+      const float time_delta = event_trigger_time - current_render_time;
       int sample_offset = (int)(time_delta * SAMPLE_RATE);
 
       // Clamp to 0 if negative (event is late, play immediately)