Dual PG279Q, Colors Different?

I just bought another PG279Q and comparing it straight out of the box, the whites definitely look different from the other.

One was made DEC 2015 and the new one is from JAN 2016.

I went through the menu and all the settings are identical. Also, the colors are still different even when plugged into the same GTX 980ti. The same effect applies when I plug one of them into my macbook pro. help?