Smelly Bosch Washing machine

I have a 4 year old Bosch WFL2450 washing machine that pongs! There's nasty build up of scum in the rubber seal, and with a torch inspection, covers the whole of the outside of the drum. We don't use powder, only liquid and have checked for blockages, all clear. After each wash I have to use to use the mini drain hose to let out the jamjar's worth of water out (which smells) otherwise the machine stinks - it's usually cloudy with bots of scum.

Any ideas?

The reason for this is you don't do a lot of hot washes and you're using liquid. (Not that liquid is a bad thing, it's just worse at causing build up and bacteria).

You'll have to carry out a few maintenance washes to get rid of the scum and smell.
Put an aerial tablet into the drum, no laundry at all, set the machine to it's hottest wash and let it run through. Aerial has a high bleach content which helps kill off the bacteria (this is the cause of the smell) and the hot wash disolves the build up of detergent and body fats.
You'll have to do a few of these to clear it then continue doing this on a monthly basis. Once clean it's easy to keep it clean.

Thanks for that - have done as suggested and a huge amount of muck has come away - looking good so far. Thanks for your comment