I have a macbook air running mojave 10.14.6.
I have a shure microphone mv5 that runs through usb c
I have a logitech webcam C615 (that has a microphone) connected through usb c.
Quicktime lets me choose both audio (computer, webcam, shure( and video (computer, webcam).
All combinations work except the one l'd like (of course) — logitech webcam for video and shure mv5 DOE audio,. When I choose that, after about 2-3 seconds, I get an error that the recording quit unexpectedly. No other info.