Aggregated devices not working.

Using Mac Big Sur 11.6 and Audacity 3.1.3 on a Mac Mini.

I want to be able to use three or maybe four identical two port audio interfaces. I have configured the aggregate in Audio Midi Set Up, have allowed Audacity to use the microphone, have selected the aggregate in the Sound file, selected it in Audacity, selected the six channels in Audacity but only the first two microphone inputs are working. Has anybody got any ideas? I’ve been through the scenario where Audacity crashes as soon as I start recording and seem to have fixed that by installing the latest drivers for the interfaces.

Windows guy here. In searching the forum, I don’t see any favorable results of people using the aggregate device on MacOS. You can search for yourself in the upper right-hand corner of this page.

From my experience on Windows, it is important to make sure that the devices are running at the same speed as specified in the software. If you don’t know what it is, you can try both 44100 and 48000, the later is preferred for video work.

Follow the Apple setup procedure carefully:

Then startup Audacity and do Transport > Rescan Audio Devices.

Note that even though the devices are “identical”, their output frequencies will drift apart.

Do the microphones all work in GarageBand?

Thanks Jademan. Interesting. I could bite the bullet and buy a multi input interface but wanted to explore the possibility that it is actually a software issue before spending the cash. I’ll try Garageband and might even have a go in Ableton but don’t want to waste too much time before deciding.

Note that even though the devices are “identical”, their output frequencies will drift apart.

Do they still ask you which device you want to use as the “master” during setup? It can only use one and the others will drift off.