Brand new iPhone 6s melted charging cable

I purchased 2 new 6S iPhones. The Apple OEM cable melted less than an inch from the lightning connector. At first I thought maybe the boys were a little rough with the cable and replaced it with a Belkin cable. Now it is melted in the same spot. These phones aren't even 2 weeks old and we've had iPhones since the "3G" came out and never had an issue like this. Both cables were plugged into an OEM wall charger.

Ideas or suggestions? Not only am I not thrilled about buying more over priced cables, this is a serious fire hazard.