Hi all. Folks have just bought new TV for living room. When the TV is on through the tuner, (ie not thru the box) a icon appears saying Nicam Stereo, and the sound quality is great. However when the box is on the same channel, or any channel, the sound is muffled and the Nicam icon does not appear. I have checked all settings with the TV and it doesn't appear to be an issue with the TV itself. Anyone any ideas?