diff --git a/DeepDrftPublic/Interop/audio/AudioPlayer.ts b/DeepDrftPublic/Interop/audio/AudioPlayer.ts
index 22d8c8a..cc0a755 100644
--- a/DeepDrftPublic/Interop/audio/AudioPlayer.ts
+++ b/DeepDrftPublic/Interop/audio/AudioPlayer.ts
@@ -140,9 +140,11 @@ export class AudioPlayer {
                     this.scheduler.addBuffer(result.buffer);
                 }
 
-                // Update duration estimate
+                // Update duration estimate — set once only; reinitializeFromOffset does not
+                // reset this.duration, so after a seek-beyond-buffer the synthesised header's
+                // shorter DataSize cannot overwrite the original full-track duration.
                 const estimatedDuration = this.streamDecoder.getEstimatedDuration();
-                if (estimatedDuration) {
+                if (estimatedDuration && this.duration === 0) {
                     this.duration = estimatedDuration;
                 }