Nothing More Than
"Affresh" except now it is being offered by P&G.
Product is nothing more than oxgyen bleach with perhaps some surfactants and other bits.
WasherhelpUK has been saying for ages, the cause of muck, build-up and odors in modern "HE"/low water washing machines is that and doing mainly warm, cool or cold water laundry with either liquid detergents and or detergents without bleach (which in that side of the pond means oxygen bleach).
Simple solution is to do at least one hot or boil wash every now and then, using a good oxygen bleach containing detergent, or add some to one's regular product.
