Additional team and channel-related features and issues within Microsoft Teams for Education
I've got a lenovo laptop and been having the same issue but seemed to fix by just uninstalling the conexant audio driver:
- right click windows icon and go to 'Device Manager'
- under 'sound, video and game controllers' right click and uninstall conexant
- once laptop restarted, in teams selected correct microphone and it worked! I also upped the microphone & boost levels in sound settings (right click speaker icon on taskbar)
random side note - previously, in the 'sounds' settings I only had one microphone listed. But after uninstalling conexant I had both the built in mic and my earphone mic listed