Hello Tom, > Could someone from Microsoft please confirm if the same is true for a > 64-bit install of Vista? Or are the shut down altogether? 64-bit MME drivers are not fully supported even in 64-bit XP and 2003 Server. In these systems, 64-bit user-mode MME drivers are not loaded for 32-bit applications (WOW64). In Vista, winmm.dll does not look for "waveN" entry, only for the single "wave" entry. If you replace "wdmaud.drv" with your driver file name, your driver will be invoked but other drivers, including WDM ones, will not be invoked. Regards, Eugene ****************** 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/