Hopefully this post isn't too basic or off-topic for this mailing list. I have developed a composite HID / audio USB device. It enumerates successfully and works. I am using the usbaudio.sys and hidusb.sys class drivers and do not have any .inf files or overtly made any registry additions or modifications for this device. But it becomes the preferred audio device and all audio goes through it. I want my application to use the device exclusively and leave the preferred audio device settings as the were before this USB device was plugged in. Also, I don't want this device to show up as a choice in the mixer at all. Is there a simple sequence of code to do this or do I need to read scads of information to figure it out? Any push towards a book, website, msdn location, etc. would be appreciated if it cannot be answered easily in this mailing list. Thanks, Mark --------------------------------- Do you Yahoo!? Exclusive Video Premiere - Britney Spears