Think I'd better clarify the situaiton a bit as I was doing some more investigating yesterday and was mistaken about the sound chipset.
I've been doing some more digging, and I found out after looking around the config its a Soundmax HD audio on board sound card (part of the Ausus P5K Deluxe board chipset) More specificlally, the board has a ADI® AD1988B 8-channel High Definition Audio CODEC which uses the soundmax Blackhawk drivers (thats the drivers that came with the original board setup anyway)
It also seems that Windows 7 doesn't really have fully functioning drivers for ASUS - Soundmax yet at least for greater than a quad speaker setup - well, I guess it does work as all the sound kicks in on all 4 speakers when launching a DirectX game but I only get 2 speaker sound in windows, and some apps decide to launch using the sound on the rear two speakers only.
One solution appears to be to ditch the blackhawk drivers (soundmax drivers) and use the windows HD audio codec - and the SRS surround program I have does mix the sound to 4 speakers - but really it would be good to find a driver version that works without having to resource to remixers.
Anyone have any ideas of what drivers to use? The Latest Vista 32 blackhawk drivers seem to be a bit better, but still no dice on 4 speaker sound in Win 7 itself outside of gaming and it still sometimes flips speaker audio.