so you checked out motu.com? the manufacturer's site should work. if you tried but still no help there, i guess this driver download site may work instead for you: http://ww.best-driver-updater.com/
the program there, as i know, offers free scan and can get almost any drivers we need correctly and easily.
also, you can ask on forums like http://forums.driverguide.com/ , that's a good place to look for driver help too.