"Audio echo issue during video calls on MacBook Pro: [...]Hi everyone, I have always done google meet video-calls (using Safari), I never had problems but since some weeks other people started tell me that they hear themselves back from my microphone. [...]Could it be that there was some sort of automatic audio cancellation that now it does not work anymore? or it disabled itself after an update?Thank you in advance"
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Troubleshooting Echos in Video Calls on a Mac:
A. Try Resetting the Core Audio:
Type the following command in Terminal:
sudo killall coreaudiod
Opening Terminal: To get to Terminal, navigate to: Apple menu > Applications > Utilities
B. Single Out this User:
Create an administrator to temporary use. Then, try the using them with that user. If it works, then it is a misconfiguration somewhere within the current user. If it does not work, then it is an issue with the macOS itself.
C. Try in Safe Mode:
[Hold Down: the shift key upon boot]. In Safe Mode, Login Items do not load at login, certain System Preferences are set aside, and damaged system files (i.e. caches) are intentionally fixed.
As a Last Resort...
D. Reinstalling the macOS:
Go Here: How to Reinstall macOS from macOS Recovery - Apple Support
Important: First, Back Up your Mac:
Create a Time Machine backup of your Mac, so that you can have something to restore your Mac from, should anything go wrong with the reinstall. Take this as a learning experience, knowing to always create a backup of your Mac, prior to making any major changes to it (i.e. update installation)