Mic Modes on the Mac
A newer feature of MacOs on newer Macs is the addition of “Mic Modes”. These are preset equalizations that change the frequency response of any microphone attached to your Mac.
As of this user tip, there are three settings:
Voice Isolation – to filter out background sounds
Wide Spectrum – to include background sounds
Standard – the “standard” mic mode.
If your microphone seems to have difficulty reproducing sounds, or cuts out at odd times, it might be due to the current Mic Mode.
To change it, select the in the menu bar and choose a new mode.
Generally, for recording – especially if it is non-vocal or musical – select the “Standard Mode.”
Here is Apple's support page for this feature: