C6300v2 wired connection stopped working twice.

Hello. I have had my C6300v2 for a few weeks, and yesterday suddenly my wired connection to the internet went out. All wireless devices could still connect fine. The light on the back of the router for that LAN port was flashing yellow.  I jiggled all the wires and power cycled everything multiple times and eventually got back online.  Then today all of sudden the same thing happens, and my wife mentions it is around the same time she happend to unplug her laptop from the wired connection and went wireless (she is on a differnet port).  Any clues as to whats going on? I have never not been able to get an IP address after plugging in a wire directly from my computer to the router, this is so frustrating.