Most bunnies hate baths and it is not recommended because they can go into shock because it scares them so much. So it’s no surprise your bunny is far from happy when even hearing the sounds.
Normally you shouldn’t have to give a full bath, and be sure to be very careful with the dryer as that can cause overheating. (just keep in on very low and don’t keep in one place for too long) You may already do this, but for anyone reading this that may not know, this is very important.
It’s best to spot clean, or just soak a urine soaked bum in a just a couple of inches of luke warm water.
I did have to give my bunny Bailey daily butt baths because she had hind leg weakness and she eventually got use to it, but unless your bunny is ill or dealing with something where his behind is messy, then that would be an exception, but of course, you would want to get to the bottom of any health issues first that may be causing that.
You said that if you put him into the bathtub he jump out real fast – have you had to give him baths often or????