Disconnect the Headset and unistall the software if any.
Go into your BIOS setup and Disable Com1 and Com2 if you have no external serial devices attached to the serial ports of your computer.
Make sure Power Management is Disabled and Plug and Play OS is NO.
Reboot to Windows Safe mode and Cleanup the Device Manager. Be sure to remove everything USB in the order given in the guide.
Hopefully, Windows upon reboot to standard mode will free USB. The intent is to get USB solo on its own IRQ.

http://www.usbman.com/Guides/Cleanup%20Device%20Manager%20Safe%20Mode.htm

Jeff Roberts
USBMan

: There are no other USB devices installed on this computer.
: USB Legacy Support wasn't enabled in BIOS. I uninstalled headset. Cleaned out Device Manager. Enabled USB Legacy Supportand rebooted. Reinstalled headset but problem remained.
: The system is a Gateway 366 Celeron. The USB host controller is an Intel 82371AB/EB. It shares IRQ 9 with the ATI Rage Pro and the IRQ holder for PCI Steering.

: : Are any other USB devices working on this computer?
: : Is USB Enabled in the BIOS? i.e. USB Leagacy or USB Keyboard Enabled.

: : Jeff Roberts
: : USBMan

: :
: : : I have Windows 98 Second Edition and have successfully installed a USB headset. Device Manager shows no warnings or errors. All of the required devices appear in Device Manager (HID compliant Consumer Control device, USB Human interface device, USB Audio Device, USB Composite Device, and USB Bulk Driver). When I go to the Multimedia Control Panel and attempt to select the USB Audio Device, it is not an option. All I can select is either the sound card or "Use any available device".
: : : Any ideas why this occurs and how to resolve it? I have reinstalled Multimedia, and all of the above-mentioned drivers. The headset works fine in another computer with Windows XP.