I have a Cubase project constantly open, and this project has as single track.
I use it to play piano in the background (without looking at the computer or turning its monitor on).
However, every 1.5 or 2 days, Cubase crashes for some reason.
Over the year there have been a few 2^31 or 2^32 samples integer wrap crashes. At least one was fixed in Cubase 12. I think you can get this within a plugin too. So one way to test this is to put the project in a different sample rate. For example 192 KHz to see if you get it quicker. 2^32/(360044100) is 27.05 hours 2^32/(3600192000 is 6.21 hours.
It depends, on how you send it. If you send it from the system dialogue, then it goes to Apple (which doesn’t help in this case). If you use the Usage Logger (Preferences > General) in Cubase, then the log files are written. Then you can send them to Steinberg Support (more details, here).
Or, you can send them here (as several other users do). We can resolve the file and let you quickly know if the crash is in Cubase or in any plug-in; if it’s a known issue, which might be fixed soon; etc. We can provide you with useful feedback, so you can maybe even fix it on your side.