I have leatherette cushions and clean them with a cotton swab soaked in alcohol (ethanol or 2-propanol usually). It worked fine so far, no discoloration on the cushions or anything. Not sure if this works for velour, though.
They probably did, but I changed apartments during the holidays, most of the boxes are still shoved in storage room, and I am just to lazy to go trough them. Their manual on internet just say to clean them with a wet cloth, but I wanted to see if anyone had any experience whit cleaning them. Advice and so...