[way2old]

Jack up vehicle and place on jack stands(safety first). Remove the wheel and look at the brake pads. See if there is any play between the pads and rotors. Sounds like the brake pad is not secured and is moving until the piston comes out and presses it against the rotor. It is more than likely something minor. If you can not see any movement, remove the caliper and make sure all the hardware is thewre to subdue the noise.