Originally Posted by cybrsage
OK, here is what I tested and my results:
All settings use PLIIx on my AVR, 6.1 speaker setup.
EDIT: I used a 5.1 soundtrack for testing and both a Blue Ray disc and a HD-DVD disc.Sound
nVidia HDMI audio control settings:
7.1 - no rear sound out of back 3 speakers except during test sounds
7.1 with rear two channels turned off - no rear sound out of back 3 speakers except during test sounds
5.1 - no rear sound out of back 3 speakers, back 2 get test sounds
2 - 2 speaker sound as expected
First off, here is what I am using:
22.214.171.124 HDMI Audio Driver
PowerDVD 7 (at 720p)
Batman Begins HDDVD - 5.1 TrueHD
I did a little bit of testing this way. I only have a 5.1 set up, so I had 5.1 selected in the driver. Problem is, the rear speakers in 5.1 aren't actually "rear" speakers. They are listed as "Side Speakers".
7.1 (All speakers on) - Sound from all 6 speakers. All 6 "signal" lights are lit on my AVR.
7.1 ("Side Pair" off) - Sound from all 6 speakers, with my rears being noticeably louder than the previous 7.1 setting. All signal lights are lit up on my AVR.
5.1 (All speakers selected) - No sound from the rears. All signal lights are lit up on my AVR.
Stereo - Comes as a stereo PCM signal and PLIIx is applied.
So, for those of you that have 5.1 disabled in your sound configuration, this might be why. 5.1 was mislabeled, and since 7.1 you can select not to have the side pair, you can get 5.1 in a round about way.
I think that this "neutering" by removing 5.1 was on purpose since it doesn't work properly. However, when I had the newest driver x.25, I did NOT have 7.1 as an option, only stereo. Of course, I was having serious problems with all my drivers at that time. I have since reinstalled Vista and am having great luck with the drivers right now, so I might try upgrading the driver. But seeing as how everything is working right now, I may not.