Smelly down there when I wake up!

So no matter what I do before I go to bed, when I wake up my crotch always smells bad. It's not a fishy or infectious , it's a strong BO/ vinegar scent. I have tried wearing loose underwear, 100% cotton, no underwear, loose pj pants, nothing on the bottom at all, I've even tried showering before bed in which case I still smell just as bad! Anyone with a similar issue who found a solution? And no, don't have an STD and I use bar soap around my labia, never inside of the delicate folds.