Anthem AVM 70

Good morning to all.

Anyone having issues with ARC not working on their new Anthem AVM 70? I've tried everything, including a lengthy phone call with an Anthem technician. Tried 4 different HDMI cables, hard reboots, factory reset, and all i get is "no signal " message on the pre-amp and television. My newer LG G4 can see the pre-amp but that's it. However, it works just fine using an optical cable. 

Any advice is greatly appreciated...Kevin