Streaming USB 1.1 devices that are connected to an external USB 2.0 hub behave incorrectly on a Windows XP-based, Windows Vista-based, or Windows Server 2008-based computer
On a Windows XP-based, Windows Vista-based, or Windows Server 2008-based computer, you plug some streaming USB devices into a USB 2.0 hub, such as a streaming USB headset or a USB camera. However, these devices behave incorrectly. This problem presents different symptoms in Windows XP and Windows Vista.
Symptoms in Windows Vista and Windows Server 2008
If the bandwidth usage of these devices is heavy, the devices may behave incorrectly.
For example, you plug a USB headset with a microphone and earphones into a USB 2.0 hub. While you listen to music from the earphones, you use the microphone to record your voice. If the music is playing at a high bit rate, and you are recording at a high sample rate, you may hear some noise from the earphones.
This problem occurs only when you plug a USB 1.1 device into an external USB 2.0 hub. It does not occur when you plug the USB device directly into the USB host controller.
For more information on this issue, including potential causes, workarounds, and resolutions, see: Microsoft KB Article KB968764.