No Primary audio in 5.1, need help..

[DodgeVader]

i just bought a new samsung bd-p1500 Bluray. I ran hdmi to my TV, and optical to my kenwood vr-209 receiver. The receiver has a Dolby digital decoder built in, but does not support DTS.

Here is my issue: I played the movie Bolt, and Punisher Warzone today, and neither would play in 5.1 audio, like my regular DVD's do. I can get 5.1 on the previews, and the menu screens, but when it comes time for the movie, I get nothing. My player has 3 audio settings, pcm, bitstream (re-encode), and bitstream (audiophile).

If I set it on pcm, I at least get 2 channels. bitstream re-encode i get nothing, and bitstream audiophile I get surround on previews and menu, no audio on movie.

Is this because my receiver isnt DTS? Do I need a new receiver? The only audio outputs from my blu-ray player is optical or red and white patch cables.

Thanks for your help!