Razer BlackWidow Ultimate

When i press the "A" key on my Razer Blackwidow Ultimate 2014, sometimes, the letter gets written twice. This is the only key it happens with. Pls help.

I have Actually 2x4 hyperx fury 1866 mhz ram , can i put more 2x4 hyperx savage 1866 mhz with no problems ... my spec fx 8350 asrock extreme 970 ed.4 gtx 970 asus psu corsair 850 rmx gold . there max speed on the rams are 1866 . i only can make them 1666 mhz but i think the system is stable ...