I upgraded the HD-DVR on DirecTV yesterday. I am getting great picture to my TV. But I am not getting sound through my home theater system, a Yamaha YHT-390BL. I have the HDMI going from DVR to Yamaha to TV. I get great picture and sound through the TV but no sound through the Yamaha. I installed an optical audio cable from the DVR to the Yamaha and I still do not get sound through the Yamaha. I have both the HDMI and optical cables plugged into their respective DTV/CBL ports. Is there something else I need to do to get the sound through the home theater system?