You don't have different sized rear tires do you on each side? That is the only thing that I can think of that would cause DSC issues. You said you replaced one of them. Did you check to make sure it was the same size as the other?
2013 E92 M3 with ESS VT2-585 SC, StopTech BBK, ESS Full Exhaust, and a bunch of carbon fiber ... - SOLD