this is for PS3 slim, not sure about fat. this assumes that your PS3's HDMI out connects directly to your receiver...
dalawa yung settings na dapat properly configured for the receiver to get bitstream signal via HDMI from the PS3.
1. VIDEO Settings -> BD Audio Output Format (HDMI): Bitstream, Linear PCM
2. SOUND Settings -> Audio Output Settings -> HDMI Out, Digital Out (Optical), AV Multi Out
->HDMI Out: Automatic (auto-enable supported formats of your receiver), Manual (selectively enable DTS, DTS-HD, DD, DD TrueHD, etc.) -> Summary of Audio Output Formats (press X to save)
possible kasi na naka-set nga to "Bitstream" yung "BD Audio Output Format (HDMI)" tapos "HDMI Out" ang naka-set na audio output, pero 2-Channel Linear PCM lang pala ang naka-enable na output format. This can happen if previously sa HDTV lang naka-connect yung PS3 and you never bothered to reconfigure "Audio Output Settings" nung kinabit na sa receiver
by the way, as of FW 3.73, while playing Bluray 3D Content DTS-HD is supported but AFAIK Dolby TrueHD is not