Washing Machine Odor

Almost all of the odor problems associated with washers are the fault of the detergent. That said, all of the detergents available today are the problem. A few years ago, the manufacturers stopped putting phosphates in the detergents; this is why we have odor problems, black scum in the drain pipes, septic field problems, and poorly cleaned clothes. We started adding a small amount of TSP (trisodium phosphate) to each load, along with the usual detergent. End of problems. No more odors, no residue, no black scum.
Yeah, I know I'll get flamed by the tree-huggers for this, but it really does more good than harm. We were starting to notice problems with our septic field until we started using TSP, now the problems have gone away.