Assuming your PS3 has the latest firmware updates, it should be connected by HDMI. Basic surround decoding is done inside the PS3 and then the PS3 will output a multi-channel PCM to the 247 via HDMI. The audio DSP within the 247 automatically will auto-detect and configure itself to play back the appropriate DSP mode.
Just my $0.02...
Just my $0.02...
