So the hot wash thing hasn't cured my smelly washing machine...

[TheNewandImprovedMrsHollywood]

... So what else could be wrong with it? Or what else can I try?

I did a 90 wash with bio powder in an empty machine. It seemed a bit better to start with but now seems smelly again.

Any thoughts at all?

is the drain attached properly. there schould be a sort of u-bend to stop the drainage smell coming back.

Have you cleaned the rubber seal, the drawer and the bit the drawer fits into? Also, have you cleaned out the filter (the entrance to ours is behind a removable kickplate at the bottom of the front of the machine)

Do a HOT HOT HOT wash with no powder and no fabsoft. Put in some old cotton towels if you have them.

If the water tuns grey and/or foamy that will be the old soap sludge coming out. Do it again until the water stays clean (indicating that it the sludge is now gone). It may take several goes. You can add washing soda if you like, it will help remove soap and grease residue.

Take out the soap drawer and scrub the sludge off it, and the aperture it fits into. Kitchen spray with bleach will kill the black mildew.

Empty the pump filter of shredded socks, lego, coins and bra wires.

Inspect the waste hose. Does it connect to the sink waste trap? If so, the hose needs to loop up so the highest point is against the underside of the worktop. If there is not a loop higher than the water level in the sink, dirty sink water will run down the hose into the washer, complete with bacon fat, tealeaves and fish heads.

Thank you ladies. I will work through all these suggestions a d hopefully be a skank no longer!