title: tokbox : Subscriber time out error on Safari
body: <p>Using opentok.js v2,  the video channel works fine with Chrome and Firefox . The opentok version used is from this link: <a href="https://static.opentok.com/v2/js/opentok.min.js" rel="nofollow noreferrer">https://static.opentok.com/v2/js/opentok.min.js</a></p>
  
  <p>But it doesn't work with safari 11.0.3.
  On session's stream created event, it generates following error message "The stream was unable to connect due to a network error. Make sure your connection isnt blocked by a firewall"
  The publisher is published successfully i.e session.publish(..) works fine.</p>
  
  <p>The code below is used to make a video call:</p>
  
  <p>this.session=OT.initSession(this.apiKey, this.sessionId);</p>
  
  <pre><code>this.session.on({
  
  streamCreated: (event) =&gt; {
  
   
  
  this.session.subscribe(event.stream, 'subscriber');
  
  },
  
  streamDestroyed: (event) =&gt; {
  
  console.log(`Stream ${event.stream.name} ended because ${event.reason}`);
  
  }
  
  });
  
  this.session.connect(this.token, () =&gt; {
  this.publisher=OT.initPublisher('publisher');
  
  this.session.publish(this.publisher);
  
  });
  
  }
  </code></pre>
  
  <p> 
  Other exceptions in console generated by opentok.js are as follows: </p>
  
  <pre><code>[Error] OT.exception :: title: undefined (1554) msg: OT.Subscriber PeerConnection Error: OT.Subscriber failed to subscribe to a stream in a reasonable amount of time
  error
  _exceptionHandler (vendor.js:150924)
  handleJsException (vendor.js:151002)
  onPeerConnectionFailure (vendor.js:162673)
  (anonymous function) (vendor.js:162414)
  onInvokeTask (vendor.js:4239)
  runTask (polyfills.js:3:10225)
  invokeTask (polyfills.js:3:16182)
  n (polyfills.js:2:31400)
  
  
  [Error] OT_ICE_WORKFLOW_FAILED: ICEWorkflow: Subscriber PeerConnection with connection (not found) failed: OT.Subscriber failed to subscribe to a stream in a reasonable amount of time
  error
  dispatchOTError (vendor.js:159161)
  (anonymous function) (vendor.js:160080)
  handleThisOnce (vendor.js:137437)
  (anonymous function) (vendor.js:137675)
  onInvokeTask (vendor.js:4239)
  runTask (polyfills.js:3:10225)
  invokeTask (polyfills.js:3:16182)
  n (polyfills.js:2:31400)
  
  
  
  [Error] OT.exception :: title: undefined (1554) msg: ICEWorkflow: Subscriber PeerConnection with connection (not found) failed: OT.Subscriber failed to subscribe to a stream in a reasonable amount of time
  error
  _exceptionHandler (vendor.js:150924)
  handleJsException (vendor.js:151002)
  dispatchOTError (vendor.js:159163)
  (anonymous function) (vendor.js:160080)
  handleThisOnce (vendor.js:137437)
  (anonymous function) (vendor.js:137675)
  onInvokeTask (vendor.js:4239)
  runTask (polyfills.js:3:10225)
  invokeTask (polyfills.js:3:16182)
  n (polyfills.js:2:31400)
  </code></pre>
  
  <p> </p>
  
  <p> 
  All the above errors  are generated only on Safari browser. </p>