ahhhhh I thought I read somewhere that LIGHT will kill the mold spores - and that maybe what's making it smell.
AT YOUR RISK - try putting a light in it - BUT WATCH IT - KEEP IT WITHIN EYE SIGHT - DON"T LEAVE THE HOUSE.
I've never tried it - just read it somewhere on one of the forums for older machines - don't know it it'll work or if it's just old wives tales.
Good luck