I received a comment back from Tech Support - it doesn't appear to have worked for me but worth a try:
Kindly go to your Personal Settings > Audio Conferencing tab https://us05web.zoom.us/profile/setting and disable this feature "3rd Party Audio".
Once done, please log out and log back in to your zoom desktop app and retest.
If issues will persist, kindly uninstall and reinstall the zoom desktop client again as per instructions here - https://support.zoom.us/hc/en-us/articles/201362983-How-to-uninstall-Zoom and retest to confirm if issue will be resolved.
Note the uninstall is targeted for a mac. Screenshots of the relevant tab attached.
Hope this helps - I'll restart now and update if it does work for me.
Okay - I found the fix. For me the issue was caused by a scheduled meeting linked to my google calendar (unsure specifically the bug but mine occurred after scheduling a meeting) that you may have made using your personal meeting ID. The personal ID was the bugged meeting for me, not any others.
So the fix should be:
1. Create a new scheduled meeting using your personal meeting ID. Just make a dummy date/time with no one else invited. Make sure down the bottom in audio you have selected computer audio. It might bring up a prompt saying this will be applied to all future scheduled meetings on this ID - GREAT!
Go into your calendar and click the link - for me, this was all it took to fix it and haven't had issue since.
Only read further if above didn't fix it.
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For me I came to solution above after a lot of other attempts. So if above doesn't work - follow steps below then go back and do above.
1. Go to https://us05web.zoom.us/profile/setting and audio conferencing tab and turn off the bullet for 3rd party audio
Log out of Zoom and back in again. If it doesn't fix it then do following:
2. Uninstall zoom and reinstall: https://support.zoom.us/hc/en-us/articles/201362983-How-to-uninstall-Zoom
3. Go back up and repeat step in top section again.
Hopefully you didn't need to read this far and calendar schedule fixed it.
Let me know if it works.