Well difficult to advise what to do for the best then. I think if it were me I would RMA the memory and then see what happens when it comes back.
Thats the funny thing, I have done it allready.
The first time I sended the Mobo to service, nothing wrong.
Next time, I sended the Mobo, CPU and ram, still, nothing wrong.
I have also tried to change PSU, Gfx, hdds and such, Its really wierd I can say.