I'm running windows 10, have a computer mic, a mic on a usb camera, and a Bluetooth headset. If I select the Bluetooth headset mic, and then in the drop down to select a different mic, webex will crash. This happens every time I try that. Additionally, if I attempt to select the Bluetooth headset, it doesn't get any audio.
Also, just now I was on a webex and was using the audio from the usb mic, and it worked for a half hour meeting, then in the next meeting it lasted about 10 minutes but then after that no one could hear me. I had to close webex and reconnect to get the mic working again. I could hear everyone else using the usb speakers with no problem.