I live in florida and 4 months ago had fiberglass insulation added in my attic over the 20yo stuff that was not sufficent. We added enough to bring it up to R45 which covered existing HVAC ductwork. Just recently some mold began appearing at a couple of the registers. I am sure the ducts we covered. Could this insulation covering the duct work be causing this mold to apprear? Thanks in advance for your thoughts.