Windows 7 - Realtek 5.1 Surround "Device In Use" problem (only stereo works)

Hi all, I've searched through the various threads on this issue, and aside from the complaining and finger-pointing, it appears 'Enhancements>Environment/Speaker Fill' seems to be the only option, which merely gives the illusion of true 5.1 surround sound.

I've just today downloaded and installed the latest Realtek driver (I think I'd forgotten to do that from since I installed the 64-bit version of Windows 7 - and yes, I made sure the Realtek drivers were the 64-bit ones, from Realtek's own website), and it didn't make any difference.

I still haven't yet figured out what it means/why it says "Device In Use", exactly? Does it basically mean they're not working for some reason?

My specs are there to see, anyway. I'll be glad to see the back of this problem for good!

ps. is there anything else I need to download other than that Realtek Driver (in the context of what motherboard I've got [or whatever] - if that makes a difference?)?

You can try using the Realtek software.
What happens when you select Environment / Room from the Realtek software, do you get the 5.1 experience?.

I suppose I do - the sound does go through those speakers anyway using that method.

Seeing as you asked that question, it sounds there's no other solution to this problem? Ah well