Recently, my rabbit has become very noisy at night. He trashes his cage, tips his litter bin, throws his ceramic food dish around, spills food everywhere, etc. It's getting to the point that I haven't had a full night's sleep in 4 or 5 days. Does anyone know why he's doing this? I've checked everything I could - temperature, bedding, litter, water, food, hay, light, sound, etc. He has toys and boxes in his cage to play with if he's bored. It's definitely not an exercise thing - for the past week (I've been off school), he has been getting over 12 hours per day of running around the bedroom. He's neutered and he's about 5 years old. I have another rabbit (his best friend) in the same room, in a different cage about 5 feet away from him. They've been in this housing situation for years. The other rabbit isn't making any noise and is acting completely normal. Can anyone help me out?