Windows 7: 5.1 Surround issue, brand spanking new system

Hello everybody,
I'm posting this evening in hopes I can get some help with a problem I've been having with my surround sound speakers.
I have a set of Altec Lansing speakers, which have worked flawlessly in the past (on a Windows 7 system I might add). I recently purchased a new computer system and now I only seem to be getting sound out of my 2 front speakers all the time, and sound from my sub only when I have my speakers set to "Ster/Surr" and not when set to "5.1 in". When I use the Realtek HD Audio manager AND the built in Windows sound components to test the speakers, they all work perfectly, and I can get the testing sound to play from each of my 5 speakers and my sub. Any games, movies, videos, music etc. I listen to however only plays in stereo.

Here is some additional information that may ease the process:
Mobo: ASUS P8H67-M Pro
Realtek HD Audio Driver Version: 6.0.1.6438
Audio Controller: HD Audio
Audio Codec: ALC892

Things I have already tried (to no avail):
-Reinstalling drivers
-Reassigning audio jacks (although as I mentioned above, the speakers DO work, they are just not receiving input for some reason)
-Downloaded the newest version of the Realtek HD Audio Manager
-Toggled and untoggled basically every audio setting I can find in Windows



As I mentioned above, I've had these speakers working on a Windows 7 system before, and I would very much appreciate any help that can be offered towards getting them to work on this system as well! Thanks in advance!

-Colin

Edit: With my last install of the Realtek driver, the HD Audio Manager seems to have disappeared from my computer?

Hi

A basic questions first: If you right click on the sounds icon in the bottom right of the screen and select your speakers. If you select 'configure', are your speakers set up as 5.1 there?

Regards
UKMedia

Yes, and when I click each speaker in the diagram to test them, they all play they testing sound properly.

Still having this problem, any insight out there?

Try unplugging all your jacks. Restart your PC.
Plug one in at a time, going through the jack detection process.
Do this for each jack you have.

Thanks for the response!

I just tried this, and no dice. All the speakers were detected as I plugged them in, and as usual, the "testing noise" played from each one, but all my sounds are still playing in stereo when my speakers are on 5.1 mode, and playing in stereo + subwoofer when my speakers are set on "ster/surr".

EDIT: Just to clarify, when on "ster/surr" mode, I'm only getting sound out of my front R, front L, and sub, however the "testing noises" will only play from front L and R (not sub).

What happens when you go to Environment and select Room?

That actually worked! I'm amazed that after days of re-installing drivers and reassigning audio jacks, it was a simple drop down selection...

Thank you so much for your help! I don't even mind that you made me look a little dumb there

Cheers mate!

No problem!
I'm glad it worked out for you.