Probably mould marks. A combination of low temp washes and biological detergents encourages a growth of slimy mould inside the drum. Do an empty wash at the highest temperature setting and put a cupful of white vinegar in the drum. The combination of high temp and increased acidity should clear it out. Do that every couple of months to keep it clear.
Repair and service your own washing machine. Go to www.2ndwave.co.uk/manual.html
dannyboy
November 2008
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