I have a funny little issue going on with my back panel USB ports.... at any given time, random ones will cease working correctly. I plug my USB devices in, and they just cut on and off, repeatedly. Mouse, Keyboard, Headphones, Cell Phone charger, doesn't matter what it is, also doesn't matter if USB 2.0 or 3.0 is plugged in, the problem seems only to persist with the 3.0 ports, as I haven't had a problem that I recall from the 2.0's.