Running Ableton Live 9, which is not compatible with Mojave. Keep having crashes, and customer support won't even respond to requests with anything other than a "not compatible with Mojave, we recommend rolling back to High Sierra" response.

Was making due, but having so many crashes, something needed to be done.

Ended up just upgrading to Live 10, because rolling back seemed such a HUGE headache. 10 still isn't "fully" compatible yet, though is apparently supposed to function fully - and haven't had a crash in a couple hours since using it, so that might have all just been the universe's way to get my ass to upgrade already... ha ha!