Make sure your USB ports aren't set to automatically to a power-saving.The settings are in Device Manager, if you don't know how to do this I'll walk you through it. Also disable the power-saving mode in the 4x4 control panel.
 
The 4x4 is what I use in my office and the 2x2 when on the road (and a 20x20 at home as a true USB 3 interface). I've used both the 4x4 and 2x2 with USB 3 interfaces without incident, but USB 3 can be a little squirrely sometimes, depending on the computer's chip set.