Is it possible for a heated side mirror to melt the plastic casing?

I purchased a 2016 QX70 and my side mirror casing melted in February and again recently. CrossRoads Infinity of Raleigh told me it was the way the sun reflected on my car. I say the vehicle, although beautiful, is Defective. I was told if it happens again, I'm responsible. I'm so disappointed. Who makes a car that can't stand the N.C. sun in February? This is some hocus pocus!

I am going through the very same thing. This started off on the passenger side view mirror. The first time this happened, Infiniti replaced the entire mirror no questions asked. Now it's happening to the drivers side view mirror and the mirror Inifiniti just replaced. They are telling me it is an outside source. I am telling them, this vehicle is parked in a garage at all times and I do not see the possibility of that happening. Will wait and find out what the dealership tells me on Monday. Will update after...