Bought a 2013 JGC new. It now has 19k and is still virtually new. I changed out the cabin air filter recently and found a HUGE mouse nest built on top of it. And of course, lots of vile stains and odors on the filter. I park it outside, but it's never been off road or parked on grass. Anyway, question is: How are mice getting into the air ducts? I can't find any obvious voids.