Sound guy who comes over and changes settings on my bass amp (EQ, etc.) without even talking to me. Before I'm plugged in, before he knows what kind of bass I have, before he knows anything about pedals, strings, setup, pickups, or 100 other variables in what will affect my signal to the board, he finds it necessary to start turning EQ knobs on my amp. Admittedly this only happened once. And admittedly, this and several other similar actions by this little dweeb almost landed a fist in his face, but this firmly counts as a pet peeve.
what?
I never had that. Ever. That's pretty weird... I had one sound guy asking me to boost the high mids onstage, but that's about it, and I didn't anyway.