One, overlooked Vista feature is the ability to set the the sound levels independently for different applications, by that I mean different volume levels for different applications that are running. If you want, you can turn the sound off for one or more apps without affecting the others.
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Click the volume icon in the system tray and under the master volume control is a link that says ‘Mixer’ click on that. (See picture)
Now you will see all the different applications that can use sound (Media Center, Windows Media Player, Winamp etc.) that are running.
Now all you need to do alter the slider for each application or check the mute box.
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