Saw a solution on the web somewhere that worked for me for colors (not whites, you will see why).

If you have stains already, I use a 50/50 of water and Tide Free and Clear in a spray bottle and I spray drench the stained area. Throw that in the washer and let it wait for wash day. Hours or days to let the Borax in it do its thing. Works great for oil stains too.

For straight up stank, like the mildew in the shoulder seams that will come out when you sweat, I use oxi in the tub with detergent, then cleaning strength vinegar (30%) in the fabric softener compartment (but not with whites and chlorine bleach, DON’T GENERATE CHLORINE GAS). Just like 2 or 3 tablespoons. You will smell it when YOU move the load to the dryer, but it mostly fades while it tumbles. The stank fades away every wash and is usually gone after 3. And it helps sanitize your washer between bleaches.