What a coincidence! Have the same problem and our white shirts were coming out with brown (mildew) spots all over them. Bought a cleaner from the ParkNshop. It smells like chlorine. It's a blue Japanese box near the washing detergents and its says its a Washing Machine Drum Cleaner. Tried it last night. Smells better but I can see some mildew around the rubber. Will do the white t-shirt test later.