obtaining a mixer for a given device interfaceGiven a mixer Device ID, you can obtain its corresponding device interface by calling mixerMessage with DRV_QUERYDEVICEINTERFACE (and DRV_QUERYDEVICEINTERFACESIZE). See the latest DDK under WDM Audio Extensions to Legacy Windows Multimedia APIs for details. This should (hopefully) match with one of the device interfaces you found from SetupDiEnumDeviceInterfaces. Jeff Pages Innes Corporation Pty Ltd