I have a (MSVAD based) USB Audio driver which I developed for our USB video adapter which works fine on all platforms until it was tested on an XP 64bit platform. There it fails to install correctly showing up in the device manager with a yellow exclamation point next to it. I won't have access to a 64-bit system on which to debug this for a while so in the meantime does anyone have any ideas as to what I may have to change in this driver to support 64-bit architecture? Steve Thorpe Empia Technology, Inc. ****************** 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/