Has he had the peeing issue since you brought him home? If not, can you think back to when it first began to see if you or your wife can pinpoint an event that may have triggered the habit? Are you using the same laundry detergent and softener you always used? Cologne, perfume? Shaving cream, shampoo, deodorant, bath soap? There's a chance that a scent is either attracting him to the clothes or he could be saying that he doesn't like some scent common to your's & your wife's clothes.
FWIW, my F6 has bouts of peeing on bath mats & kitchen towels. After the vet determined he didn't have physical issues, I used Dr. Elsey's cat attract until he stopped peeing in the wrong places. With Taji, his peeing on fabrics always coincides when he's upset about something -- most often when I come back from a trip or when I don't play with him enough.