Is there an acceptable decibel level for music in the gym

[bacon]

Is there a level that is classed as too loud? Loud when the instructor is shouting and screeching through the mouthpiece?

Who checks the standards of fitness instructors in the LA gym? Who do they rely on the feedback (if any) from the participants?

I personally would e-mail your concerns, say it makes the class uncomfortable to take part in and the whole point of the mouthpiece is that they don't need to shout. There is motivating people and there is pissing them off and leaving them unable to concentrate on the moves in a safe fashion.
I have myself done so just this week about an instructors insistance that she is the best at everything she does and no instructor teaches the classes properly! Its a shame as I have had to drop 5 classes as its people I consider friends she is slating.