Lightest sleeper ever

Someone please help! We love in a small apartment, less than 800sq feet. My toddler has always been the lightest sleeper ever. Even as a newborn. And we always made sure to make noise and get him used to sleeping with noise. It never worked!! Problem now is that when he's in bed I can't do anything! And once he's awake he's so upset screaming he never gets back to sleep no matter what I try. I can't even flush my toilet without him waking up crying. I was putting clothes away and I have to do everything so slow and quietly and I barely made any noise closing the drawer because I did it so slow and he still woke up. Nap time is a nightmare because if the mail comes he wakes up. If I cough rooms away he wakes up. Everything wakes this kid up. I have to be absolutely silent and I can't do anything or get anything done! The kitchen is the furthest room away and most of the time even doing dishes will wake him.

He has a white noise machine! And it's on LOUD and I've tried several! And different settings!! What do you do about light sleepers!?