I have Windows 10 and a USB mic headset that I have used with Audacity consistently. Of course, the realteck computer mic and the camera mic show up in the new “Audio Setup,” “recording device” selection menu.
I learned previously that I must insert the USB mic before opening Audacity. However, now, once I select the USB mic, Audacity will NOT record. Subsequently, neither will it play. The program has to be closed and re-opened to get any response.
Looks like maybe it is a bug? Of course, my podcast is held up until this can be solved one way or another, because the built-in mic is not sufficient.
So this could all be in the timing. When you plug in your USB mic, it takes a few moments to be recognized. Also, when Audacity scans for audio devices, this takes a few moments. If closing Audacity, then restarting it fixes the issue, this may be the case.
Also, it may be a little quicker to do Transport > Rescan Audio Devices, which will do the same thing.