How concerned are you guys about noise while you're fishing? I've heard more times than I can count about how easy crappie are to spook. I know people that if they snag a brush pile, they'll move to another spot immediately, without waiting to see if they messed up the spot. I've also been with guys that would run back and forth over a brush pile using a big motor wide open trying to locate it, and fished them very successfully. I've also heard guys say you should turn off your sonar, because that can spook the crappie (I don't believe that, but maybe I'm wrong).

Do you make sure you don't bang around the boat?
How deep is a brush pile, before you'd drive over it?
Do you keep your voices down?
Does noise really only matter if they're not biting well?

Please share you're opinions.