Discovery of the day: I can use Audio Hijack with ScreenFlow to record the Mac audio from the Finch Pixel USB-C1,2 mic and the Mac screen. Why use Audio Hijack? Well, so that it can use the macOS Voice Isolation feature and output the results to the Mac audio, which the special audio driver of ScreenFlow, in turn, picks up. Without this, ScreenFlow 10.0.9, with direct voice isolation, creates distorted sound.
With the Lightning version, I had no issues with the iPhone 13 Pro, macOS Voice Isolation and Screenflow. The problems come from using USB (A or C) microphone devices. It’s a known issue, apparently—no fix in sight. ↩︎
I spent way too much time and money trying to fix the sound quality for my recordings. ↩︎