As dumb as this sounds, I have been in this house 4 years and the wife just tells me she thinks something is wrong with the dryer! I check the dryer vent on the side of the house (two stories) and note the one way flap is not open with the dryer on! I find it stuccoed shut! I clean around the flap to allow airflow. There is none with the dryer on! Where is this thing venting? How do I find the break and do I have to start tearing up the walls in order to make repairs? Who in the trades handles this problem? Thanks..