We have recently just bought a samsung htx250r home cinema. we have a 50 inch samsung plasma, the dvd player sound works using the hdmi cable but the surround sound does not work when we are watching...
Really this is a question of sources. The reason your able to hear surround sound when connected to your DVD player is that is what is providing your audio and video source. When your watching television it would depend on how your getting your broadcasts. If you are either receiving an over-the-air broadcast or cable directly to your set, your television becomes the source. As your television is providing the signal, you would need it to loop back to your receiver to provide that surround sound.
Now for the good news, if you have a cable or satellite box these should have outputs to connect to your receiver to provide the audio source.
Also keep in mind not all broadcasts provide a version of surround sound. Most newer home theater systems will replicate surround sound artificially.
I hope this helps.
Go Ahead. Use Us.