I have the upgraded BMW performance drilled and slotted rotors. These were just installed a couple months ago and I wash my car weekly. All of the holes in the rotors have filled up flush with brake dust and ive tried everything to get it out. APC nor Iron removing wheel cleaners will get rid of it. I have to literally go in there with a pick and clean it out one hole at a time if i want them clean. Is there a cleaning product to help get all that dust out of there or should I just ignore it? really pissing me off. Thanks all.