Odd brake related noise

Okay this is really starting to bug me. First a little history…

Vehicle is a 94 Suburban. The front brakes were done approximately 14K miles ago. Rear about 10K miles ago. Ever since the front brake job (new rotors, pads) there has been a sound, sort of like spring tension being released whenever I (quickly) release the brake pedal. I think I notice it now more than ever because I don’t have working ac and the windows are usually down. The thing is, if I slowly release the pedal I hear nothing. When it does happen it is definitely coming from the front and is more predominant (I think) on the right side. So far I have yet to hear this sound coming from any other vehicle stopped beside me in traffic so something must be out of whack.

I mentioned this to the mechanic who did the brakes (only shortly thereafter) and he checked it out and said nothing was amiss.

Recently I had new tires installed so I asked the (different) mechanic to check the brakes again (front and rear). Apart from cleaning out the drums and a minor adjustment on the rear they said everything was good. Now I’ve never had any issues with stopping and I’ve had a few hard braking episodes without incident but this snapping noise for want of a better description is driving me nuts. One final observation: I cannot get the ‘sound’ to occur when I am sitting in Park and depress and then quickly release the brake pedal.

Could be some sort of “rattle” or noise from the pads shifting in the caliper that only happens when the rotors are spinning. That’s why you can’t duplicate it at rest.

The sound only occurs when I am completely stopped at a traffic light or stop sign and then lift my foot quickly off the brake pedal to proceed. It happens exactly when I get off the brake in a hurry -especially when I’m first at the light. If I get off slow ie.back in a line of traffic, little or no sound. It’s like a sharp release in brake pressure is being translated into the clack? sound somehow. The faster I get off the brake from a stop, the louder it is. If this is a loose pad what is the remedy? Replace?

"The sound only occurs when I am completely stopped at a traffic light or stop sign and then lift my foot quickly off the brake pedal to proceed’

That should be pretty easy then to find noise making part. Use parking brake and wheel stops. caliper, engine mount and u joints would be my first thoughts.