I don't mind noodling at rehersal if nothing better is going on. I recently got a new distortion pedal and I was trying to dial it in but every time I did anything both the drummer and guitarist started noodling. I had it dialed in for my practice amp. I kept asking them to be quiet for a few minutes, but that lasted about 10 seconds. Eventually I just gave up and was pretty annoyed the rest of rehersal because now I had to try to dial it in during songs. It took the entire session before I even got close.
People should be able to give you a little peace to make some quick adjustments in rehearsal, within reason. But this is the sort of thing you should work out at home, IMO. Expecting the band to put things on hold because you don't know how to dial in your gear is not a good use of rehearsal time.
Wait for a break and use that time to work out technical difficulties.