My Grovia training pants that I use at night were similar when I started using them after quite a few washes it stopped but I think one of the problems were the layers weren't drying properly and they r made of hemp which has a more stinky smell. I washed mine and double rinsed and let them dry outside then popped them in the dryer with a cloth with a few drops of lavender oil to help the bad smell that worked for us but I have friends who love super undies and haven't complained about any smell so I hope it can be fixed for you