Stinky laundry

Lately I've had a problem with my clean laundry coming out smelling like rotten garbage. I'm wondering why this would be and if it has something to do with my washer. Any ideas?

 

I'm just going to venture a couple of wild guesses. Is it possible a piece of laundry (a sock?) could be lodged under the agitator and is molded? Is the drain functioning properly. It should be 2" pipe and be trapped near the floor. Perhaps there is a blockage in the drain and gray water is getting into the washer. As I said, these are wild guesses, it will be interesting to hear what it actually is. Likely some of the pros will have first hand experience with a problem like this.

 

Trap

Often it's because there is no trap. It can also occur if the drain hose goes into the pipe too far and the hourse drainage system backs up occasionally. If you have a trap is there water in it?