[scarecrow420]

And you still haven't tried playing the file locally?

If he can play back okay with OpenElec then the problem has to be windows drivers or some other configuration problem.

yeah so playing local file under windows would start to narrow down what element of the windows configuration is not happy (eg network drivers would be ruled in/out)

although really we know the drivers are fine since a lot of us are running XBMC on NUCs with windows with no major issues. My bet would be on XBMC configuration (eg audio settings) or perhaps just hasn't installed all the correct drivers (IME, Graphics Driver for HDMI audio etc)