Mouse in dash?
 

I just bought a 2001 boxster a week ago. Last night when I was sitting in it with the engine off reading emails, I heard a very quiet scratching and clawing noise coming from the HVAC vents. I could have sworn it was a mouse in the dash chewing on the foam inside. I pulled the cabin air filter and found some pieces of fabric that could have been chewed off and placed there by a mouse but no obvious nest or mouse feces. Today I parked the car in the driveway with the top up. It was almost 90° out today so the cabin got pretty toasty to say the least. I was hoping the high temps made the critter leave from where he came. Now I'm afraid he died in there or hes just still in there. Anybody have any thoughts, comments or suggestions? Is it even possible for a critter to get in there? Where could it possibly be?