rewash towels with HOT water, detergent and add bleach..you might also want to run your washer with one cup of bleach and hot water ( empty, no clothes) to clean the machine out as well and get rid of any musty odors (and bacteria)
Ree

I had the same problem and started putting less clothes in my washer, and using less detergent. That did it. Once in a while I get that same smell and realize I need to go back to putting fewer clothes in. Worth a try.

I get a product from SAMS club called OdoBan. It comes in a gallon jug usually with a full spray bottle attached.
I fill my fabric softener dispenser with it and use a little less detergent and the towels come out soft and fresh smelling.

Are you in a location where you can try natural outdoor direct sunlight?

Cautiously, it may bleach some materials.

Also..front loaders are known to get a sour smell..( I am not sure if this is what you have) it's because the door is sealed tight when shut..no air gets inside, after you do a load, you naturally close the door and the inside is not dry, so it will smell after a while...It is also good to clean out you machine as I have posted earlier on..also vinegar after a bleach wash (empty) will help it a long as well as clean out the hoses..
Ree

How about this? I have a moldy smell in some of my clothes but not others. More specifically in some of my polo type shirts but not others. It's bad enough that I can't wear them. I can wash two shirts in the same load - one will smell, the other will not. I should also mention that it's the same 3 or 4 shirts that smell every time. I'm guessing they got moldy at some point and the mold is still there. Any help would be much appreciated.

"OFTEN, forget to take it out of the washer and put it in the dryer."

Run that load through again with hot or warm water and a cup of ammonia. Usually works for me. (BTDT) Or, set a loud timer to let you know when the load is finished so you can get it out before it smells ;-)

zjdeere- I had the same problem with a pair of jeans- the smell increased over a short period of time. The jeans were practically new and I didn't want to throw them in the trash. I got on the Laundry forum and several people recommended Charlie's Soap- after a few washes with that detergent they quit smelling and I keep using that detergent and they haven't smelled since.

The only thing we could think of was maybe something used in the manufacturing process of the clothing.

I can also recommend Charlies Soap and multiple washes. It even gets rid of the smell of feces. Don't ask how I know, but it does.

Add a little Lysol all purpose cleaner to your detergent and let it soak for a little while.

I'm with summiebee, my sisters and I were all complaining about our towels and thought it was the dye maybe. Ditch the liquid soap and go back to powder. We have had no problems since.

Dacron or other fibers of that family ( it's been too long, I forget it it's a polyester or another classification) hold smells and stains more than cotton or other man made fibers.
That may be an explanation for why some shirts smell and others don't.
Linda C