We recently purchased a 50' Samsung TV and in trying to set up our Yamaha RX-V496 Reciever with our Sony DVD Player. Both have DTS Decoders. But what happens is when you start to play a movie on the DVD player you get sound but when the menu comes up and you select DTS and play the movie now you have no sound.
Are you using digital/optical cables into the receiver? Are they connected properly? Is the receiver on auto detect?
Then proceed here. Go to the set up menu of the DVD player...make sure there is no disc on the tray.
Go to the Audio options. You should be able to see Dolby Digital, Stereo, PCM, DTS, etc. Activate the DTS, for some reason this option is not on by default from many DVD players.