Loopback
Used by 2 peoplerogueamoeba.com ↗

“Over on the Mac, I host guests in a Zoom session (I don't like Zoom - it's annoyingly fiddly to set up for good sound and the company's pronouncements don't fill me with joy - but it tends to be software that people already have, so I use it) and route the sound hither and yon with Rogue Amoeba's Loopback.”
Piers Cawley Interview, Carer, singer, photographer, streamer · via Uses This