Could be grease, bits of rubber seal breaking away or old soap scum which may be cleared if you do a really hot wash & put in some descaler (same as used to clean dishwashers) or some washing soda. Run the cycle (no washing in it). If still there then it may be one of the other two.
Lincoln Appliance NZ
June 2009
check your detergent dispenser for mould - that was a problem with mine. A good clean did the trick and now i remove the drawer after every wash to allow it and the inside to dry.
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