It sounds like you have the red,white rca cables hooked from the back of the tv to the red,white input on the stereo or the same connection from you hd sat box or hd cablebox. In order to get the same sound quality from tv service as you do on dvd is to run a fiber optic cable or digital coax audio cable from you hd sat box or hd cablebox to your stereo which means no red,white rca cables at all, take them out. Also once you do that you must be on a hd channel to get equal sound quality of a dvd movie. I know on some hd cable or hd sat boxes you have to go in and set them up to dolby digital as well after you hook it up the way I was explaining. Try this and I hope this is helpful.
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