更糟，现在连电话铃也不响了，显示这样的错误信息，怎么办？

Call Failed

We are not able to start audio on your computer. Please check the audio device settings on your computer and make sure you have a working speaker and microphone. You must also allow the use of the microphone for this call when prompted by the web browswer. You may return to the last page and try again.

可是

我的mic可以录音（用windows自带的录音软件），录音完后可以回放听到录音效果。