My issue isn't as powerful as yours, but definitely having crashes occur when the system is doing many tasks. Could run Premiere export or MP4 conversion in the background while streaming on my iMac Pro 128GB Mojave when using OBS V1 23. Ever since I update to OBS 2, if I am running Chrome (which I have a lot of windows open) or try and do high intensity exports, guaranteed to hard crash about 90 min-2 hours in. Crashes seem to have propagated to other software, as I am now having issues with Zoom I didn't have before, as well as Adobe Premiere. Can't 100% say it's OBS 2, but it sure seems like it.
Makes me wonder if your issue has anything to do with either RAM or graphics card. On my system, I have 3 monitors connected, which I think is the max the iMac Pro can handle. If OBS 2 altered something with graphics, or does something intense with graphics that OBS 1 didn't do, that might explain it.
