If you're using Vista, you might have noticed that you can't change the volume using the "Windows Mixer" remote control section.
Actually, the volume do change, but for the application itself. BTRC is not generating any sound, this is particularly not useful. Vista's got a new feature that allows the user to control the volume of applications independently, which is pretty cool from the user point of view.
But from the developer's perspective, this modifies a bit the way for setting the sound volume. The "old" api still works but for the current application; and if you set the application in Windows XP compatibility mode, the behavior will be restored. Since I don't want to set that compatibility mode, I had to add specific support for vista using the new IAudioEndpointVolume, COM interface (COM, when'll that disapear...) that allows getting back the original behavior, which is changing the master volume.
It'll be in the next release.