Sandy got one of those Dance Dance things but she bought some sort of pad that went under it that was supposed to diminish how much the sound carried through to the floor below. Maybe you could ask them to buy one of those pads? Normally I would say 7:15pm is too early to complain on a weekend night but if it is literally giving you a headache that's different. Maybe they could at least turn the music down a little. Yech.