First, the pads are brand new and both rear rotors were turned. I've been having a weird 'pop' or 'creak' sound from my driver side rear for a while (before and after new pads/rotors). I'm stuck trying to figure out the noise but I noticed a difference in the patterns left on the rotors. Also, I regreased all the slide pins in case that was the issue. It looks like the top portion of the rotor with the issue is bouncing or something? Anyone have any ideas?