c media xp driver semi works

I believe I need notification of an update to the High Definition (C-Media 9880) motherboard sound driver. The one installed by Vista insisted I was using a 3-plug output which I could not configure (therefore where my existing speakers were attached it assumed were 'surround' speakers).
I installed the latest available from C-Media, which failed - then I was prompted to re-install using recommended settings. This proceeded well, and the control panel now allows me selection of which devices are output and so forth. Most importantly, it believes I have only a pair of speakers instead of 4.1 or 5.1, whatever the defaults were.
Now I cannot run the C-Media applet that appears in the taskbar (failure to run a DLL as an executable), and intermittently, adjusting properties (like volume level) using the Vista control panel causes BSOD.