Thanks for all your replies.
Yes I always leave the door open and dispenser tray out.(Note: Dispenser area has no smell, it seems to come from the drum)
The machine is not integral.
I have not investigated a 'Drainage sump' I take it that's different from a filter, neither of which are located at the bottom of my machine.
They come with VERY flimsy instructions these days, just a paper sheet with basic instructions, so I will look online to see if I can find this sump. I'm just so fed up of the smell when I've always done EXACTLY as I did with my old machine, funnily enough that one DID get a bit of mould on the door, but NEVER smelled !