at about 10k kms I noticed whenever moving slowly I'd hear a loud noise coming from the brakes. Sounds like my rotors are rubbing on the pads. I take it in and they tell me our cars uses metallic brake pads so as they get contaminated with oil, dirt etc they become noisy. They sanded the pads down to get rid of all the grit and it seemed to help for a few days but now it's back. Anyone else having this problem ?