Oh boy. a two for none sale!! Fire them both!Ok, I'm dealing with an extremely loud drummer and guitarist. For some reason, they can't grasp the concept of letting the PA do it's job!! Drums just slams on his snare. We play on a small stage and he gets frustrated when told to control his volume. Guitarist is just loud! Plays the wrong chords and chunks along needlessly!
Seriously, record a song on stage from the house with them playing as loud as they usually do. Keep your’s and everybody else’s volume to an appropriate level. Then play it back for them and ask the question, “Does this sound balanced to you?” If they say yes, there is no cure.
As for your drummer’s frustrations playing quieter, like your frustrations don’t matter?