This is exactly what I did and it worked great on 5 pairs of stinking
cotton socks. If you have more, increase the amounts....
Set a 1-2 gallon plastic container in the sink, bathtub or outside. I
used one with a lid so it wouldn't smell up the place overnight.
Add 1/2 gallon of hot water
Stir in 1 cup distilled white vinegar. Use real vinegar, $2/gallon at
SLOWLY add 1/2 cup of baking soda stirring as you go. It foams up a
lot, so start with a tablespoon and increase from there.
Add your regular amount of laundry detergent and dissolve.
Fill to 1 gallon with hottest water you can and mix.
Immerse each towel one at a time.
Let it soak overnight.
Dump towels and everything in the washer and wash in hottest cycle. No
need to add more detergent or anything else.
Dry in dryer until completely dry. Online says "hot" but I dried them
with no heat - ran dryer twice as long, but I didn't want to shrink the
socks, and it worked fine.
Other method says hang on clothesline in the sun - good idea if you can.