It looks like the flight recorder data has been reviewed, and an Airbus official quoted with "....a serious final assembly quality problem."
Airbus admits to A400M assembly problems | Business | DW.DE | 29.05.2015
Several reports have suggested a temporary loss of power to three engines, which just strikes me as an odd number. I could see one, two (same wing), or even all four being subject to software or otherwise issue, it is just that three, if confirmed, strikes me a bit more odd or unprecedented. Just a point of interest- no theory- no blame, just caught my eye.