Ironically, I have now found out that the problem was my M-Audio Firewire Solo which I used for the sole reason of having phantom power on it. I have now bought a mixer which I have plugged directly into my soundblaster Audigy 2 ZS. Whilst the Creative drivers have had to be updated due to all the revisions and updates that microsoft make to their operating system I don't think that Asus boards are the problem as that Asus boards are all I have ever used and creative cards have always worked for me.
I think the issue with the M-Audio Firewire Solo could well be to do with the firmware updates that it does automatically. It works fine with my mac but on all the PC's I have used it on now it has the same problem.
I am upgrading to vista which I will be using in the next few days. I am aware that there are beta drivers available for the SB Audigy 2 ZS so I will let people know how these drivers are with the OS.
Cheers