I recently purchased a USB Microsoft Wireless Multimedia Keyboard 1.1. It works fine except for the volume control, which does not function at all. The mute button works and displays the volume meter on the screen, but the volume up and down buttons do nothing. I have searched around online, and most of the information I have found suggests a human interface driver problem. It looks like I have the latest versions, however, and Windows Update cannot find any new files. I am running XP Pro with SP3. I attached a screen shot of the device manager. The first "HID Non-user Input Data Filter" does not seem to control anything, but disabling the second "HID Non-user Input Data Filter" causes the mute button on the keyboard to stop working. The "USB Human Interface Device" appears to control the mouse. Any suggestions?