Last year, I've risked washing a pair of pads (DT-990 Edition) and the inlay manually, in lukewarm water with "Perwoll", having replacement pads as "backup" of course. After rinsing and gently pressing the water out, left to dry naturally. The good thing about it: the pads became "as new", at least optically, they did not seem to have suffered any "structural damage" either. The bad: they needed three days to dry. I think those pads have "normal" foam, not "memory" foam, but I'm not sure.Not supposed to but some become really grudge and the stuff you use to clean them cab have an influence on the foam/cover material.