My buns have both decided to chew everything tonight including the TV stand, skirting boards and even their litter trays. They've got some chew toys but the only one they use is a chew mat. The problem is they make such a banging noise using it I have to take it off them at night for fear of upsetting my downstairs neighbours! What do your buns like to chew? I need a quieter alternative for the evenings!