Ok I have no personal experience with your cans but they come well recommended…better for tracking than mixing though from what i gather.
In any case it’s possible that monitoring through your recorder is clouding the issue too.
By the way if you are doing your final mix on your pc (it’s not standalone) using your cans check these out. A mobile mix engineer mate of mine swears by them…
http://uk.focusrite.com/usb-audio-interfaces/vrm-box