97db,
If you really want to hear the DD and DTS tracks, you'll need to go through your DVD player setup menus and set the player to "video" or "video only". This disables the DVD-A part of the player and you'll be able to access the other formats through your digital connection. You'll probably need to restart the disc after you find the proper setting.
One point about the 6 channel direct input on the 950, make sure you switch to it from a multichannel input or format. If you switch to it from a stereo source , say CD or Tuner, you'll only get two channels out of your DVD-A even though the source is sending six channels.