It's Day 3 and it's still working!
I have clumping litter. I clean it once, sometimes twice a day. I add baking soda. I clean the actual plastic box. I have a window and a ceiling fan in the same room and yet, I can't get that awful fermented litter, poop miasma from permeating the whole damn house!
I put a small cup of vinegar on the corner, on the floor, just out of cat's way. The smell stopped instantly! Even in the morning, when it's at it's grossest, the litter smell doesn't go much beyond the doorway! Once it's clean again, no smell at all!
I don't know how long this will last but this is awesome!
Yes, there is the faintest vinegar smell inside the cat bathroom but it's not overpowering and it doesn't effect cat behavior.