My PS3 is hooked up to my TV with HDMI and an optical output to my Yamaha receiver. I have set the sound settings on the PS3 to reflect this. While playing games or watching REGULAR DVD's in 5.1, my Yamaha shows 5 speakers in use but while playing Blue rays, I only get two speakers showing in use. Left and Right only. Any ideas? Why can I get the right sound with regular DVD and games but not with Blue Ray?? HELP!