I used to have a Sony DVD player and when I got my 1050, I had to change the audio output on the DVD player to allow the 1050 access to the 5.1 (or whatever it might be) signal. It'll be in the manual on how to set this up.

According to the listing on Deep Discount DVD, The audio format of Seinfeld (Season 1 & 2) & Frasier (Season 1) are both Dolby Digital Stereo (which I think just means 2 channels) and Friends is listed as Dolby Digital 5.0.