[zbuttram]

Yep, happens any time the AirPods mic is activated on MacOS, has been that way since launch as far as I know. Doesn't happen on iOS. I can only assume it has something to do with the Bluetooth hardware or they would have fixed it by now.

[geerlingguy]

But it usually goes back once the mic is no longer being used. And I've had it happen a few times where I take a 'continuity phone call' from my iPhone on my Mac. The AirPods switch to the low-quality call mode, I have my conversation, I hang up, and the audio quality still stays switched until I do the Audio MIDI workaround or reboot.

Most of the time that doesn't happen, though—when I hang up the audio goes back to normal mode (48 kHz). So it seems to be a weird bug with the switching that I've only ever seen on the Mac (works perfect on iOS).