One thing that is not a solution, but helps with the problem here in the humid southeast..

Many times it's so humid I run the AC on recirculate for better cooling while driving.. but I have learned to always switch the AC control back to the "outside air" position when the vehicle sits overnight, so there is an open path to the outside for the water in the AC unit to evaporate back to the outside..

I find the stink from the AC unit to be much less when I do this.. Have also sprayed Lysol in the AC intake with the fan running at times.. There are other sprays made for this purpose.