fix(audio): Prevent events from triggering one frame early

Events were triggering 16ms early in miniaudio playback because music_time
was advanced at the START of the frame, causing events to be checked against
future time but rendered into the current frame.

Fix: Delay music_time advancement until AFTER rendering audio for the frame.
This ensures events at time T trigger during frame [T, T+dt], not [T-dt, T].

Sequence now:
1. tracker_update(current_music_time) - Check events at current time
2. audio_render_ahead(...) - Render audio for this frame
3. music_time += dt - Advance for next frame

Result: Events now play on-beat, matching WAV dump timing.

1 files changed, 8 insertions, 3 deletions

diff --git a/src/main.cc b/src/main.cc
index 89e21f1..4922d69 100644
--- a/src/main.cc
+++ b/src/main.cc
@@ -125,12 +125,13 @@ int main(int argc, char** argv) {
     }
 #endif
 
-    // Calculate delta time and advance music time at scaled rate
+    // Calculate delta time
     const float dt = (float)(t - g_last_physical_time);
     g_last_physical_time = t;
-    g_music_time += dt * g_tempo_scale;
 
-    // Pass music_time (not physical time) to tracker
+    // CRITICAL: Update tracker BEFORE advancing music_time
+    // This ensures events trigger in the correct frame, not one frame early
+    // Pass current music_time (not future time) to tracker
     g_audio_engine.update(g_music_time);
 
     // Fill ring buffer with upcoming audio (look-ahead rendering)
@@ -138,6 +139,10 @@ int main(int argc, char** argv) {
     // acceleration/deceleration At 2.0x tempo, we consume 2x audio per physical
     // second, so we must render 2x per frame
     audio_render_ahead(g_music_time, dt * g_tempo_scale);
+
+    // Advance music time AFTER rendering audio for this frame
+    // This prevents events from triggering one frame early
+    g_music_time += dt * g_tempo_scale;
   };
 
 #if !defined(STRIP_ALL)