title: OpenTok failing to add Subscriber video after establishing session on Cordova Android
body: <p><strong>Issue</strong>  </p>
  
  <p>Subscriber video for device not being added to dom element after establishing OpenTok session.</p>
  
  <p><strong>Expected behavior</strong></p>
  
  <p>After the OpenTok <code>session</code> receives the <code>streamCreated</code> event:</p>
  
  <ul>
  <li>subscribing the session to the <code>event.stream</code>,</li>
  <li>passing in the target dom element,</li>
  <li>providing the subscriber's properties, and</li>
  <li>providing a callback</li>
  </ul>
  
  <p>should initialize the subscriber stream and populate the provided dom element with the video stream or fail if an error occurs during the subscription process.</p>
  
  <pre><code>this.session.on({
      streamCreated: event =&gt; {
          console.log('----- Event Stream: ', event.stream);
  
          let subscriberProperties = {
              width: '100%',
              height: '100%',
              insertMode: 'append'
          };
  
          this.subscriber = this.session.subscribe(event.stream, 'subscriberContainer', subscriberProperties, err =&gt; {
              if (err) {
                  console.log('----- Subscriber subscribe error: ', err);
              }
              else {
                  console.log('----- Subscriber added.....');
              }
          });
      }
  });
  </code></pre>
  
  <p><strong>Actual behavior</strong></p>
  
  <p><code>streamCreated</code> fires and the stream is created. OpenTok throws a warning:</p>
  
  <pre><code>RTCIceServer.url is deprecated, please use RTCIceServer.urls instead.
  </code></pre>
  
  <p>Followed by these errors:</p>
  
  <pre><code>Error while setting RemoteDescription
  </code></pre>
  
  <p>--</p>
  
  <pre><code>DOMException: Failed to set remote offer sdp: Session error code: ERROR_CONTENT. Session error description: rtcpMuxPolicy is 'require', but media description does not contain 'a=rtcp-mux'..
  </code></pre>
  
  <p>--</p>
  
  <pre><code>PeerConnection.offerProcessor Error while setting RemoteDescription: OperationError: Failed to set remote offer sdp: Session error code: ERROR_CONTENT. Session error description: rtcpMuxPolicy is 'require', but media description does not contain 'a=rtcp-mux'.. in state
  {
       connectionState: undefined,
       iceConnectionState: "new",
       iceGatheringState: "new",
       signalingState: "have-remote-offer"
  }
  </code></pre>
  
  <p>--</p>
  
  <pre><code>OT.exception :: title: Connection Failed (1013) msg: OT.Subscriber PeerConnection Error: PeerConnection.offerProcessor Error while setting RemoteDescription: OperationError: Failed to set remote offer sdp: Session error code: ERROR_CONTENT. Session error description: rtcpMuxPolicy is 'require', but media description does not contain 'a=rtcp-mux'..
  </code></pre>
  
  <p>--</p>
  
  <pre><code>Unhandled rejection null
  </code></pre>
  
  <p>--</p>
  
  <pre><code>OT_SET_REMOTE_DESCRIPTION_FAILED: SetRemoteDescription: Subscriber PeerConnection with connection (not found) failed: PeerConnection.offerProcessor Error while setting RemoteDescription: OperationError: Failed to set remote offer sdp: Session error code: ERROR_CONTENT. Session error description: rtcpMuxPolicy is 'require', but media description does not contain 'a=rtcp-mux'..
  </code></pre>
  
  <p>The subscription error comes back as:</p>
  
  <pre><code>{
      code: 1501,
      message:"SetRemoteDescription: Subscriber PeerConnection with 
          connection (not found) failed: 
          PeerConnection.offerProcessor Error while setting 
          RemoteDescription: OperationError: Failed to set remote offer 
          sdp: Session error code: ERROR_CONTENT. Session error 
          description: rtcpMuxPolicy is 'require', but media description 
          does not contain 'a=rtcp-mux'.."
      name:"OT_SET_REMOTE_DESCRIPTION_FAILED"
      stack:"Error: SetRemoteDescription: Subscriber PeerConnection with 
          connection (not found) failed: PeerConnection.offerProcessor 
          Error while setting RemoteDescription: OperationError: Failed 
          to set remote offer sdp: Session error code: ERROR_CONTENT.                         
          Session error description: rtcpMuxPolicy is 'require', but                         
          media description does not contain 'a=rtcp-mux'..↵    at 
          file:///android_asset/www/src/scripts/opentok.min.js:1:365616    
          at S.it 
          (file:///android_asset/www/src/scripts/opentok.min.js:1:545734)    
          at 
          file:///android_asset/www/src/scripts/opentok.min.js:1:252654
  }
  </code></pre>
  
  <p>Both publishers on the web and device send the outgoing streams and properly establishes. The web subscriber properly receives the stream from the device and establishes. The device subscriber does not receive the stream, errors out, and never establishes.</p>
  
  <p><strong>Notes</strong></p>
  
  <p>Outgoing streams are fine. Both publisher streams are established and the subscription stream on the web portal end is established. The incoming subscription stream is never established on the device.</p>