Audacity dies when attempting to record

I sure hope someone has already solved this problem. I am running Mac Mojave 10.14.2 and Audacity 2.3.0. While attempting to stream record from my Allen & Heath Qu-Pac (16 Channels) via a USB B connection, as soon as I select record in Audacity it completely closes Audacity. If I attempt to record 14 channels it seems to work perfectly. Any ideas of what is going on?

Thanks, Phil

From the lack of replies, I guess the answer to that is that no-one knows.
Have you made any progress with this?

No real progress so far. If I select 15 or fewer tracks it seems to work. If I select 16 tracks and one stereo track (17 and 18) the LR main from the Qu-Pac it also seems to work. A work in progress for sure.