I live in the Detroit area. Humidity all over the map from 50%-95%. I have an attic installation of my a/c system (radiant heat). I have insulated round ducts running off of two metal duct conduits, one at each end of my house. Paint bubbled under one of the metal ducts, I shifted it, pulled back the insulation and noted a water stain in the sheetrock. I’m thinking it is condensation on the cool metal duct falling to the corner then dripping. I’m thinking insulating the exterior of the metal duct will fix the problem. I’m worried that the water is from within the metal duct and wrapping it in isulation will just create a moldy mess for me down the road. Can anyone provide any guidance or practical exprience?