We've confirmed some mice in a different room, chewing through the wall around the dryer vent. I'm convinced whatever's making the loud noises is something bigger than mice, though. I went to Home Depot and bought some mousetraps and rat-traps. The mousetraps are the new ones with the newfangled plastic cheese-shaped bait shoe. I'm skeptical; I wanted the original metal-shoe ones but that's all I could find. It actually looks like a somewhat better design because it forces the mouse to actually step on the shoe and not just stand there licking it. I got original victor rat traps too, to put in the bathroom ceiling. They had electronic pest eliminator things....since we can't get in the walls after the pests, maybe that would actually be a good solution, assuming they work. For $40, I think I'll wait.