Then unmap the device that you are using (USB interface) to avoid kmixer. Instructions:
Go to Control Panel - System Hardware - Device Manager - Sound Video and Game Controllers (your device) - Right-Click and select Properties - Audio Devices (your device) - Properties - Set "Do not use audio features" and set "Do not map through this Device"
Interesting Steve N. would doing the same thing be beneficial for: XP based PC/external hard drive wireless router Squeezebox Duet external DAC? I assumed that I was bypassing my PCs hardware/audio devices????