Windows Vista - http://www.vistaarticles.com
No Audio Playback from USB Device
http://www.vistaarticles.com/articles/208/1/No-Audio-Playback-from-USB-Device
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Published on 12/10/2006
 
There is no longer any audio playback.

No Audio Playback from USB Device

To work around this problem, stop and restart the media player OR restart the computer after every time that you unplug a USB audio device.

When you stop and restart the media player or restart the computer, the audio project is reloaded. When the audio project is reloaded, the playback graph is rebuilt to render audio for the audio device that is currently plugged in.