SIP.JS 0.11 FREESWITCH 1.6音频问题

Question

我正在尝试将sip.js 0.11与FreeSwitch 1.6一起使用，但是在建立呼叫（接受）时它没有音频。进行保留时，音频将起作用。经过测试：Chrome 70和电子3。

APP代码：

• USERAGENT

  userAgent = new SIP.UA({
  
      uri: user+'@'+url,
  
      transportOptions: {
          wsServers: ['wss://' + url],
      },
  
      authorizationUser: user,
      password: password,     
      register : true,         
  }); 
  
  userAgent.start()
  

• 拨打电话

  var sessionDescriptionHandlerOptions = {
  
      constraints: {
          audio: true,
          video: false
      }
  
  }
  
  var session = userAgent.invite('sip:'+number+'@freeswitch_server', 
  sessionDescriptionHandlerOptions);
  

• ATTACH_MEDIA

  session.on('trackAdded', function() {
  
  
          var pc = session.sessionDescriptionHandler.peerConnection;
  
  
          var remoteStream = new MediaStream();
          pc.getReceivers().forEach(function(receiver) {
              remoteStream.addTrack(receiver.track);
          });
  
          remoteAudio.srcObject = remoteStream;
          remoteAudio.play();
  
  
          var localStream = new MediaStream();
          pc.getSenders().forEach(function(sender) {
              localStream.addTrack(sender.track);
          });
  
          localAudio.srcObject = localStream;
          localAudio.play();
  });
  

HTML

<video id="remoteAudio"></video>
<video id="localAudio" muted="muted"></video>

非常感谢！