You know, you have the exact setup that I purchased initially. The TV's HDMI (ARC) and the Sony soundbar HTNT5 would sometimes work together fine, sometimes not at all. I tried several brand-new cables to see if that was the problem - no it wasn't. It would work fine at night, and then would not work together early next morning. I thought that the HTNT5's HDMI ARC input was defective, so I returned the HTNT5, and upgraded to the Bose 300 soundbar. The Bose and the 850D TV worked fine, after giving me a few scares when it didn't work a few times.... It now works fine. You know, I think it is the TV's HDMI ARC input that somehow has a glitch. I got Geek Squad coverage for both TV and soundbar for 2 years, so I don't have to worry about it anymore.