Fix voice change bug

web/pages/Assistants.tsx

@@ -1336,6 +1336,9 @@ export const DebugDrawer: React.FC<{
       // Start every text debug run as a fresh session transcript.
       setMessages([]);
       assistantDraftIndexRef.current = null;
+      // Force a fresh WS session so updated assistant runtime config
+      // (voice/model/provider/speed) is applied on session.start.
+      closeWs();
       if (textTtsEnabled) await ensureAudioContext();
       await ensureWsSession();
       setTextSessionStarted(true);
@@ -1608,6 +1611,14 @@ export const DebugDrawer: React.FC<{
     });
   };
 
+  useEffect(() => {
+    if (!isOpen) return;
+    if (!wsRef.current || wsRef.current.readyState !== WebSocket.OPEN) return;
+    // If core TTS-related settings changed while drawer stays open,
+    // reset the active WS session so the next launch uses new metadata.
+    closeWs();
+  }, [isOpen, assistant.id, assistant.voice, assistant.speed]);
+
   useEffect(() => {
     if (!textTtsEnabled) {
       stopPlaybackImmediately();