diff --git a/talk/app/webrtc/objc/avfoundationvideocapturer.mm b/talk/app/webrtc/objc/avfoundationvideocapturer.mm
index bd472a498a..d68fdff79a 100644
--- a/talk/app/webrtc/objc/avfoundationvideocapturer.mm
+++ b/talk/app/webrtc/objc/avfoundationvideocapturer.mm
@@ -142,6 +142,7 @@ static dispatch_queue_t kBackgroundQueue = nil;
   if (!_isRunning) {
     return;
   }
+  [_videoOutput setSampleBufferDelegate:nil queue:nullptr];
   AVCaptureSession* session = _captureSession;
   dispatch_async(kBackgroundQueue, ^{
     [session stopRunning];
diff --git a/talk/examples/objc/AppRTCDemo/ios/ARDVideoCallViewController.m b/talk/examples/objc/AppRTCDemo/ios/ARDVideoCallViewController.m
index b12a61a618..2f07c7a4cc 100644
--- a/talk/examples/objc/AppRTCDemo/ios/ARDVideoCallViewController.m
+++ b/talk/examples/objc/AppRTCDemo/ios/ARDVideoCallViewController.m
@@ -151,8 +151,10 @@
   self.remoteVideoTrack = nil;
   self.localVideoTrack = nil;
   [_client disconnect];
-  [self.presentingViewController dismissViewControllerAnimated:YES
-                                                    completion:nil];
+  if (![self isBeingDismissed]) {
+    [self.presentingViewController dismissViewControllerAnimated:YES
+                                                      completion:nil];
+  }
 }
 
 - (void)switchCamera {