mPaaS音视频通话音视频 web版本demo黑屏问题怎么解决？

mPaaS音视频通话音视频 web版本demo黑屏问题怎么解决？
Uncaught (in promise) TypeError: Failed to execute 'getStats' on 'RTCPeerConnection': parameter 1 is not of type 'MediaStreamTrack'.
at RTCPeerConnection.getStats (adapter.js:445:33)
at RTCPeerConnection.getStats (adapter.js:607:31)
at meeting_api.js:1:198655
at new Promise ()
at H (meeting_api.js:1:198505)
at Object.QFWxl (meeting_api.js:1:248794)
at [as executeStat] (meeting_api.js:1:273492)
at ne. (meeting_api.js:1:288732