Hi, Sorry for my last empty post... My question : Can the driver (or the .inf file) decide about the values of the GUID's created in [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\MMDevices\ Audio\Render ? I ask this question because in XP the GUID's are created with just incrementing the GUID by 1 for each device installed, and under Vista and Win7 there is always a totally different value used. As a result when you use DirectSoundEnumerate() the devices are ordered by GUID and you have not the same behaviour under XP and Vista. Markus. ****************** WDMAUDIODEV addresses: Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx Subscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=subscribe Unsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=unsubscribe Moderator: mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx URL to WDMAUDIODEV page: http://www.wdmaudiodev.com/