How do you get that smell out?

If you wash them and dry them thoroughly they shouldn't smell. Keep towels in a dry linen closet or closed in a cabinet. Towels not dried completely or that are kept in a damp room will get musty.

Put a little bit of dishwasher detergent in with the towels next time. My sister had a problem awhile back with musty smelling sheets. They had gotten wet and sat for awhile in her basement and they started to stink even after being washed.

Dishwashing detergent contains very little actual detergent, it's the steaming hot water that does most of the cleaning in a dishwasher. What it does contain is anti-sudsing agents and a compound to break surface tension which reduces spotting and increases the effectiveness of the hot water. So D/W detergent is pretty effective at removing soap scum which can act as a petri dish for some kinds of mildew.

I usually hang my towels to dry after using them in the shower rather than just tossing them in the hamper. They don't get that musty smell as often as they do if i just dump the wet towel in the hamper.

I use sunlight detergent or homemade detergent. I HATE buying laundry detergent its so expensive.

Any cloth would definitely smell musty or worse, smell like cockroach if it's folded or shrunken or left twisted when wet. They even develop molds or the tiny black dots that are not eraseable. In our home, we don't put our laundry in the basket if they are wet or damp. We hang them to dry out then, that's the only time. We even hang them outside if the sunlight is good to eliminate the weird smell.

Add vinegar - a half cup or so - to the rinse cycle.

I get a funny smell sometimes when I have washed and dried clothes, I always think that it reminds me of wet dog. When I get this smell on things I just clean my washing machine out and all the pipes and then it usually goes.