turn speaker on in video call.

lib/modules/cx_module/chat/calling/call_provider.dart

@@ -88,6 +88,7 @@ class CallProvider with ChangeNotifier, DiagnosticableTreeMixin {
     onSuccess = null;
     isMuted = false;
     isPeerMuted = false;
+    isSpeakerOn = false;
     // `CallProvider` is a long-lived singleton (registered once in main.dart),
     // so without resetting these here, toggling the camera off near the end
     // of one video call would leak into the *next* call, making it look like
@@ -176,6 +177,9 @@ class CallProvider with ChangeNotifier, DiagnosticableTreeMixin {
         case RTCIceConnectionState.RTCIceConnectionStateConnected:
         case RTCIceConnectionState.RTCIceConnectionStateCompleted:
           if (currentStatus != "Connected") {
+            // The OS resets the audio route to the earpiece once media
+            // actually starts flowing, so re-apply it on connect.
+            _applyDefaultAudioRoute();
             _setStatus("Connected");
             _startCallDurationTimer();
           }
@@ -201,11 +205,23 @@ class CallProvider with ChangeNotifier, DiagnosticableTreeMixin {
       // on this singleton CallProvider (see endSession()).
       isCameraOn = true;
       isPeerCameraOn = true;
+      isSpeakerOn = true;
       await _webRTCService.initializeForVideoCall();
       _webRTCService.setCameraEnabled(true);
       notifyListeners();
     } else {
+      isSpeakerOn = false;
       await _webRTCService.initializeForAudioCall();
+      notifyListeners();
+    }
+  }
+
+  void _applyDefaultAudioRoute() {
+    if (isVideo == true) {
+      isSpeakerOn = true;
+      _webRTCService.setSpeakerphoneEnabled(true);
+    } else {
+      _webRTCService.setSpeakerphoneEnabled(isSpeakerOn);
     }
   }
 

lib/modules/cx_module/chat/calling/webrtc_service.dart

@@ -269,6 +269,9 @@ class WebRTCService {
         );
       }
 
+      // Video calls should use the loudspeaker, not the earpiece.
+      await setSpeakerphoneEnabled(true);
+
       _isFullyInitialized = true;
 
       if (!_initializationCompleter!.isCompleted) {