fix: make soundtrack loading terminal

src/audio/soundtrack-engine.ts

@@ -387,7 +387,9 @@ export function createSoundtrackEngine(
       mainSource = main;
       mainSchedule = schedule;
       attachMainEnded(main);
-      for (const source of introSourceNodes) {
+      const committedIntroSources = introSourceNodes;
+      introSourceNodes = [];
+      for (const source of committedIntroSources) {
         source.stopAt(transitionTime + EXIT_CROSSFADE_SECONDS);
       }
       loadedIntroBuffer = null;
@@ -456,22 +458,24 @@ export function createSoundtrackEngine(
     void mainPromise.catch(() => undefined);
 
     if (activatedFromStart) {
-      loadedIntroBuffer = await dependencies.loadBuffer(context, sources.intro, signal);
+      const [introBuffer, mainBuffer] = await Promise.all([
+        dependencies.loadBuffer(context, sources.intro, signal),
+        mainPromise,
+      ]);
       if (closed || signal.aborted) throw abortError();
+      loadedIntroBuffer = introBuffer;
       if (latestChapter.atStart) {
         transportStarted = true;
         startIntro(loadedIntroBuffer, context.currentTime + SOURCE_LEAD_SECONDS);
         return;
       }
+      transportStarted = true;
+      startDirectMain(mainBuffer);
+      return;
     }
 
     const mainBuffer = await mainPromise;
     if (closed || signal.aborted) throw abortError();
-    if (activatedFromStart && latestChapter.atStart && loadedIntroBuffer !== null) {
-      transportStarted = true;
-      startIntro(loadedIntroBuffer, context.currentTime + SOURCE_LEAD_SECONDS);
-      return;
-    }
     transportStarted = true;
     startDirectMain(mainBuffer);
   };
@@ -514,6 +518,16 @@ export function createSoundtrackEngine(
       mixer.dispose();
       for (const source of [...ownedSources]) source.cancel();
       ownedSources.clear();
+      pendingIntroExit = null;
+      introSourceNodes = [];
+      introProgramGain = null;
+      mainSource = null;
+      driveLiftSource = null;
+      afterglowSource = null;
+      mainSchedule = null;
+      mainBufferPromise = null;
+      loadPromise = null;
+      exitLoadRequest = null;
       context.removeEventListener('statechange', onStateChange);
       stateListeners.clear();
       outputGain.disconnect();