I started using Relab Development's LX480 Essentials back in around October of last year. I really liked the sound and in testing it was running relatively fine.
Somewhere around that time projects started "crashing" for me. For context, I use Logic Pro in Native mode on an M1 Mac and usually the way it "crashes" is when it force-reloades the project. The pop-up says:
Now, if I chose "recover" Logic would force-reload the whole project and every single time I lost adjustments to plugins. Instruments were reset fully sometimes. Everything Logic hasn't yet saved automatically was fully lost. I had to find the preset again or recreate what I made again - It was incredibly annoying.An Audio Unit plug-in reported a problem which might cause the system to become unstable. Please quit and restart Logic Pro.
buttons: Recover or Quit.
In January I bought Sonsig Rev-A. It sounded beautiful and I still love it (though I wish it had a monochrome UI option instead of purple and also HiDPI support).
When I tested it, it was doing relatively fine, but once in a while these "Audio Unit plug-in reported a problem..." messages started appearing again. At first I didn't understand what the cause could possibly be, until I started taking plugins off...and I still couldn't pinpoint the cause. Even after fully removing a Relab plguin from a project these messages would continue appearing.
...Until I discovered that if I saved the project with no Relab plugins, fully closed the DAW and reopened the project - the issue was gone.
I also remember reading on some forums that Relab plugins crashed their projects too, so I guess I'm not the only one having this issue.
I haven't emailed Relab yet, but I don't know if this will ever be fully fixed. After all, this is not one product, these are two different ones, but I guess they share some codebase (if that's the correct way of putting it) and somewhere in there lies the reason why this is happening. I assume it has something to do with M1 (arm) support.
It's really sad that I have to stop using these plugins now. I love their sound, but when this happens several times in a row always in projects with Relab plugins and the problem goes away after doing what I described above, for me that is clear that they are the problem for now.
I hope someone can share their experience about this too.