Rubber seal
This is how you clean behind the seal: open the door to your machine and clean the back of the rubber seal with a scrunched up piece of paper. There’s a good chance a lot of grey stuff will come off. This is a mixture of hairs, skin flakes, encrusted soap residue and bodily greases, which gets left behind if you wash on low temperatures a lot or use too much laundry detergent.
