HIWe have a 2009 32BDHS North Trail. WE park it seasonally.WE have mice!We have blocked any holes with steel whole. We have used moth balls.We think the mice are coming in from the black under belly and have chewed a hole in the flex able duct for the furnace. The mice travel thru the trailer using the furnace duct work. Does anyone have any suggestions for us?Should we remove the black membrane and replace the duct with a metal one? Has anyone done this before? Is this even possible? Maybe there are spots the mice are getting in that we haven't located and perhaps someone else on here has had this same problem.Any suggestions at this point would be helpful! Thank you