fix: register audio event handlers before setting src to avoid onloadedmetadata race

frontend/src/pages/Speakers.tsx

@@ -74,12 +74,11 @@ export default function Speakers() {
           return;
         }
 
-        audio.src = blobUrl;
-        audio.load();
-
         await new Promise<void>((resolve, reject) => {
           audio.onloadedmetadata = () => resolve();
           audio.onerror = () => reject(new Error("Audio decode failed"));
+          audio.src = blobUrl;
+          audio.load();
         });
 
         if (!cancelled) setAudioLoading(false);
@@ -181,6 +180,7 @@ export default function Speakers() {
         onTimeUpdate={(e) => setCurrentTime(e.currentTarget.currentTime)}
         onLoadedMetadata={(e) => setDuration(e.currentTarget.duration)}
         controls
+        preload="auto"
         className="w-full mb-3"
       />