I used to have this problem in my old appt… unfortunately I was on the other end. I just didn’t realize how loud she was for those few short seconds… until the upstairs neighbor pounded on the floor. Once it was brought to my attention by somebody not my roomate, I told her to STFU and bite the pillow. They are not doing it on purpose… you said they were quiet for a week after you banged on the wall… maybe just a reminder that they are loud would be enough to quiet them down.