HT

tomstat

I have an HT-NT5 and XBR65X850D connected via a high-speed HDMI cable through the ARC HDMI port of the TV.
When it works, it's fantastic. But about every third time, despite all setting that I know of being correct, I get NO sound. I can switch back to TV sound with no problem. But when I switch back (using "synch Settings in the Action Menu on the TV) nothing. The only solution is literally to do a full unplug it/power-off of the TV, let it reboot and then the synch works fine....for another 1-3 power-ups. I've spoken to SONY and they've escalated this to "upper-level technical" but I've gotten no solutions or answers yet.
Strategies, solutions, thoughts?  Looking for a permanent fix that allows me to use my set-top box (Xfinity X1) remote volume control.