Problem with PS3

I have my ps3 connected with HDMI to a sony HDMI receiver. STRDE800 i beleive. I get dolby 5.1 with Blu-ray movies, but when I play a game i only get 2ch PCM, anyway to shut off PCM completely? The audio is being output on a Fiber cable to the receiver since my receiver states that audio through hdmi is only going to come out of my tv's fiber port. Also, in the menu when your supposed the hear the Click when you scroll the XMB it is sporadic at best.