If your microphone is unavailable, verify your permissions on your Mac or Windows, and in Chrome.
Mac Users
The permissions for MacOS can be found under System Preferences > Security & Privacy > Privacy.
Select Microphone.
Select the checkbox next to an app to allow it to access the microphone.
Windows Users
Start or Windows search: Microphone privacy settings and ensure Microphone access is enabled.
Your microphone settings in Chrome can be found here:
chrome://settings/content/microphone
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