public static IDeviceTopology DeviceTopology(this MMDevice device)
{
var attribute = typeof(IDeviceTopology).GetCustomAttributes(typeof(GuidAttribute), true).Cast <GuidAttribute>().FirstOrDefault();
if (attribute == null)
{
return(null);
}
var pInterface = device.Activate(new Guid(attribute.Value), CLSCTX.CLSCTX_ALL, IntPtr.Zero);
return(Marshal.GetObjectForIUnknown(pInterface) as IDeviceTopology);
}