If you are using the built in ATSC (high def) tuner then you are receiving the Dolby Digital surround broadcast through the television as well, which tries to pump everything possible through the TV speakers, which isn’t always a bad thing, but because the broadcasters are trying to make the experience bigger for the viewer at home it sometimes poses this problem. You will also experience this through external sources like satellite and cable as well. The best way to defeat this is to adjust your sound settings on your television – you may even want to disable the surround sound function on the set. The sound will still be stereo, but the TV will not try as hard to create the full effect. With your Hitachi set you’ve got the ability to change quite a bit with the sound, so you may want to adjust it there. Also check the settings in the tuner to set the output to stereo instead of surround sound, this will also help.