on the face of it, that’s totally bizarre.
but it makes sense if you had engine.cutoff = in the last launched script. when you do sleep, norns remembers the last script you ran; on wake it looks this up and runs the script again, and in this case i’m guessing re-borks the engine method.
(again, its strange to me that you can’t un-bork it just by switching to a different engine and back; i really will look into this and maybe try to make engine methods un-settable with metatable hacks. but i am heavily occupied at the moment with other tasks.)
when you kill the matron process, or use the rude power button, the script isn’t saved; norns notices this on startup and doesn’t launch any script (the assumption being exactly that you are recovering from some pathological state brought about by the last script .)