Media keys control system and Winamp volume.
 

I have a multimedia keyboard with a volume wheel and play buttons, etc. Unfortunately, the volume slider adjusts the volume in both winamp and windows 7, which is rather annoying when trying to adjust the music volume in the background while gaming.

I would like to make the volume slider only control the volume in winamp and not the windows system volume, does anyone know how his might be done? All the info I've been able to find is about how to make it work the opposite way and only control windows.