How to mute your Mac’s microphone for every app at once
Open System Settings › Sound, choose Input, select your microphone and drag Input volume all the way to the left. Every app then hears silence — until you drag it back, or until an app that adjusts the level by itself turns it up again.
The built-in way
- Open System Settings › Sound and, under Output & Input, click Input.
- Select your microphone and drag Input volume all the way to the left.
- Remember to drag it back after — and know that some call apps adjust the microphone level automatically and turn it back up by themselves.
To take an app’s microphone access away completely: System Settings › Privacy & Security › Microphone.
The one-click way
Questions
Does it work with headsets and USB microphones?
Yes. Still Studio silences every input on the Mac, including one you plug in after you muted.
Will the people in my call notice?
They hear silence, the same as when you use the call app’s own mute; the call itself keeps running.
Does closing the lid mute the microphone?
Yes, on a MacBook: closing the lid disconnects the built-in microphone in hardware. A headset or USB microphone still works.