i have noticed a few days ago, after i heard some strange noise when braking hard, that both front rotors have some strange marks on them. The brake pads seem to have at least 1/3 left but still i get the noise when braking hard....should i change the rotors as well? the lip on the rotors is barely noticeable when i cross my finger over...both brake pads and rotors are OEM ...last time when i changed the front control arms i took a look at the pads and they seemed to have all kind of little cracks, i guess this could be the cause of the marks? i've never tracked the car nor did i heat up the brakes...