Easy enough fix - I've had to do it at least 7 times - wear rubber gloves if you want as it can be quite a mucky job & it's not necessarily a job for the squeamish due to the disgusting gunk - disconnect all hoses (have a washing up bowl ready for any water left in pipes), disconnect mains plug, move machine out of where it lives. Tip machine forwards & put a large old towel under the machine. Remove plastic panel at bottom of machine - held in place with a few self tapping screws. You'll see a black rubber hose in bottom of machine which the drain hose joins onto, this in turn is attached to the pump & motor - carefully disconnect the multipin connector - it pulls apart - make sure you hold the plastic connector, not the wires. The hoses are held in place with large worm drive type (jubiliee) clips. Loosen these (2nd one is on RHS & slightly hidden from view) - there's no need to undo them completely. Wriggle & twist the hoses off the bottom of the drum & the flatish drain pipe carefully, there will still be water in it.
Inside the large rubber housing you'll see a 'ping pong' ball & no doubt a load of crud including coins, buttons, 3 inch nails from husband's boiler suits etc - remove all this, you can also remove the hoses from the pump & give it all a good flush through with clean water, including the main drain hose - you'll be amazed at how much crud & slime builds up in the hose - if using a corrugated hose stretch it all the way along it to help dislodge as much muck as possible. Refit everything - make sure you grip the jubilee clips firmly as you re-tightenthem so you keep the screwhead within easy access.
I tend to run the machine through part of a wash cycle before putting it back in its slot, leaving the drain hose low to help if flush any last remaining muck out.
Oh & I'm female & I've just finished doing it as I had white bits appearing on all the washing this week - took me about 10mins once I'd moved the machine out :)
Lesson to be learnt - don't buy a machine without the front filter - I certainly won't ever buy another 'self cleaning' machine!
v8kate, October 2011