Had my rotors cut and pads changed to pass inspection recently.
Now, every time i back up(AND ONLY WHEN I BACK UP, NEVER GOING FORWARD) and apply the brakes, this noise like something rubbing on something starts(aka the music)
i take it back to the spot, sure enough they say its the rotors.
How can i be sure who the cuprit is, the rotors or the pads?
Could the process of cutting the rotors been botched, or do i have cheap pads?

Changing the oil tomorrow at the dealer.
Gonna ask their opinion on this matter also.
Thought i would try to get some help from here first.

Anybody......?!!?