MS keyboard 6000

I have two of these, from the same store, exact same model. Strangely, they function in different ways. Specifically, the zoom buttons are different. On one, pressing up increases the zoom, pressing down decreases the zoom. On the other one, the opposite is true, pressing up decreases the zoom, pressing down increases the zoom. is there a modification to it so that pressing up increases the zoom, pressing down decreases the zoom for both keyboards?