Did anyone see that episode of dirty jobs were Mike the host was working with the crew of guys that was useing the spray in insulation inside of walls of new homes This insulation was sprayed from the floor to the ceiling and packed tight and trimmed flush. Were im going with this is , in the show they hade a bucket lined with this stuff and took one of those alarms ,that hurt your ears that women carry for when they need help or to scare off an intruder,and tossed it in. They put a lid on it and you wouldnt believe how much noise it cut down you almost couldnt here it. Cant remember the name of the type of insulation this was, maybe one of you contractors could help,but maybe you could line a box or cabinet with this stuff and make a large kill box for it.