[Uridium]

Optical (Toslink or digital Co-Ax) does not have enough bandwidth to carry DTS-MA or Dolby TrueHD formats.

The PS3 is outputting these over HDMI to your TV but the TV isn't capable of passing these through to your surround system.

You can check what format the PS3 is outputting by pressing select during BR playback and looking at the audio codec dispalyed at the top of the screen.

Afraid your not going to be able to get HD audio formats so you will need to choose the standard DTS/DD soundtracks.