I would run a cycle with just hot water and bleach. Pick the highest water level available and just use a cup or two of bleach, I assure you is won't ruin anything.
My washer was doing that not all that long ago, I did the bleach thing as my mom suggested and made sure that as soon as a load was done washing, I put it directly into the dryer; seems I have a small drip as well that is keeping the clothes inside it wet, and if I forget there's something in there until the following day, all the clothes smell nasty. I have to rewash and immediately move them into the dryer. So I also recommend you don't leave anything sitting in your washer.
Also if you ave rust problems, a cup of SnoBowl run through a cycle with just water works wonder to remove it!