[sylware]

In the end, I have strong suspicions on the unity game engine, some weird 'timing' stuff would be happening here, which would disrupt the boss pattern 'timings'. In your case, it seems it is "amplified" by the wayland compositor you are using (I guess you tested various compositor libraries, because many are based on the same libs... where could be hidding some latency, like is xorg but a bit more accute).

But as I said, in my personal case, I have to account for my stress intolerance which is significant, which does not help narrowing down those type of issues. Then, I am probably not one of the right guys to figure out that, but I'll do tests here and there to see if I can get some pertinent info.

I suggest you do the same than me anyway: shutdown all apps, and disconnect your network cable.