I have an application which has sound. I have a global property to mute the sound. The problem is, there\'s so many different things which can make sound, I would hate to it
XP does not support per-application volume control. That capability was added in Vista. So what you are attempting to do cannot be done in XP by fair means.
There is software called IndieVolume that retro fits per-app volume control to XP. I can only imagine it does so by means of low-level hacking, DLL injection and so on. I doubt that's really an option for you.