I bought my RS6 with JHM 2-piece lightweight rotors already installed. I have been hearing a scraping noise from the front brakes when cornering hard and finally found the source. The rotor is not centered in the brake caliper and is much closer to the inside of the caliper than the outside. This allows the inner brake pad guide pins at the bottom of the pad to contact the rotor when it flexes due to heavy cornering forces. There is a witness mark on the inside edge of the rotor that matches the size and location of the pad pins on the caliper.

I can't find any discussion about this issue. Is this a known problem?

I filed about .050" off the inside pins on the caliper to give additional clearance and that appears to have fixed the issue when cornering moderately hard, but I suspect they will still contact the rotor if I really throw it into a corner, which kinda defeats the purpose of having a sharp handling car with sticky performance tires.

The proper fix appears to be to shave 1-2mm off the caliper mounting bracket where it bolts to the upright to move the caliper inward and center it on the rotor. A quick and dirty fix would be to put a 2mm spacer behind the rotor to space it outward, but that will reduce the contact area between the center bore of the rotor and the hub. This is a small enough contact surface already and I don't want to reduce it any further.

I should have snapped some pics when I was working on it last night as they would show the issue clearly vs. trying to explain it.