Brakes?

I have an annoying problem. When I hit the brakes to slow down or stop, and then get back on the gas to drive, I will hear a dull sounding pop. It sounds like the pads aren't releasing from the rotors when I get off the brakes and hitting the gas to make the wheels move makes the pads release causing the pop. I don't know what it is, but it is annoying. I have a 96SL manual.
Thanks for the responses ahead of time.

hmmm, i have a similar problem, but i dont know if i ever posted it. My problem is taht sometimes, when im stoped or slowing down, and then accelerate, when i go from 1st to 2nd, theres like a creaking metal sound...it happens just as the car catches second gear and bucks alittle with the change...

Mine usually pops when im backing up..every time i do