It seems like a common problem that causes smelly laundry is detergent buildup on the clothes. We were definitely having this problem with our old washing machine that didn't spin well. It's much better now with our new machine. We also switched to using Charlie's Soap on everything (though I know some people have given it lukewarm reviews, and it doesn't perform well in hard water, it's wonderful for us.)
And thanks for the link to "machine care." My new front loader wants you to clean it with bleach, but I don't use bleach-- now I'll just use bs and vinegar. That'll work the same, it sounds like.