So a couple weeks back i noticed wood shavings and some insulation "pushed" out of my fireplace vent...odd. there is no debris in this pic, but this is where it was






Then there was more yesterday. I set a trap. Boom.



Set another one for tonight. I need to find the external breach.
Wherever this internal breach is, I won't find it. It's likely behind the fireplace.

So this should keep me busy for a while.