Hey Buront
I apologise for going MIA
Have been rushed the past while
Ok there is some good news and some bad news
These
C-Media Drivers seem to rectifying the exact same issue you have however it looks like the C-Media devices for vista are becoming corrupt somehow and people are finding buying a new sound card the only option
Try updating the drivers again in device manager
Start and type
Device manager and hit enter, Go down to the driver with the exclamation mark and select
Update driver
Then post the driver details here for me, It does however look like a hardware issue with the actual sound card
Regards
Craig