diff --git a/src/bot/orchestrator.ts b/src/bot/orchestrator.ts
index fcbe9ea..458b0de 100644
--- a/src/bot/orchestrator.ts
+++ b/src/bot/orchestrator.ts
@@ -72,6 +72,7 @@ export class BotOrchestrator {
   private _isShuttingDown: boolean = false;
   private _isDebugMode: boolean = false;
   private _keepAliveInterval: NodeJS.Timeout | null = null;
+  private _hasAttemptedMicEnableForTts: boolean = false;
 
   constructor(
     sessionId: string,
@@ -828,6 +829,20 @@ export class BotOrchestrator {
       return;
     }
 
+    // Best-effort safety net:
+    // In some authenticated sessions the mic can be muted after join.
+    // TTS is injected into the mic stream; if mic is muted, participants hear nothing.
+    // We only attempt this once per session to avoid unnecessary UI actions.
+    if (!this._hasAttemptedMicEnableForTts && this._teamsActions) {
+      this._hasAttemptedMicEnableForTts = true;
+      try {
+        const micEnabled = await this._teamsActions.toggleMic(true);
+        this._logger.info(`TTS preflight mic-enable attempt result: ${micEnabled ? 'ok' : 'not-confirmed'}`);
+      } catch (err) {
+        this._logger.warn(`TTS preflight mic-enable attempt failed: ${err}`);
+      }
+    }
+
     await this._audioProcedure.playAudio(audioData, format);
   }