The cooling in the rooms is ok. I think the damage happened during installation of the ductwork when the house was built 15yrs ago. Some of the plastic covering got torn and over the years the heat helped it along.
During the home inspection (3yrs ago) the return duct had a very large hole causing the a/c unit to take in attic air. We actually had a second inspection to verify the a/c system was still ok. Additional ductwork was found to be torn. Those sections were replaced.
Now I'm getting ready to blow more insulation to the attic and found a couple sections torn. I'm probably over-reacting by replacing the original duct work. I just do not want to have to replace any more ductwork after the insulation gets installed.