so not too long ago i posted about how to get rid of mice and i got a lot of good advice. the visible mice are now all gone. however, lately i've been hearing them INSIDE THE WALLS at night. how the heck are they getting there?! and how do i get them out?! i can hear them scampering and squeaking at all hours of the night, and my roomate's bf seems to think their chewing is the reason our heat no longer works upstairs. how do i get these little buggers out of my house?!