Nevermind I figured out my own question, a new firmware update does allow the x3 to act like a usb dac. It may not technically be out yet it seems.
That's cool, maybe it will supersede the e17 quality wise in this aspect.
Kind of offtopic sorry. I would be interested in using the x3 with the ma900 in usb dac mode and see how it does any chance you could try that matt ?
Edited by kcee - 10/19/13 at 10:00am