System setup

Setup question...
Sharp Aquos LCD, Cable Box, DVD player
I wanted to hookup HDMI cables from the devices to LCD and 1 optical cable from the LCD to the YSP-800. But I get no sound through the dvd player, the cable box works great. Tried switching the HDMI inputs, too. Problem is with the dvd player, no sound. I tried two different DVD players, a panasonic dvd player and the sony playstaion 3. I had success once with the sony playstation3 after playing with the audio setting on playstation but I tried another movie and some games but no sound. Has to be something simple I am missing :)

Thanks