Controller disconnects and reconnects every 5 mins or so?

I always have my controller connect with the cord with no batteries in it, since i got the xbox 6 months ago, It is 360 pro white with the same white controller, never had a problem with it. Now when i play xbox games,(NHL and MW3), it will pause the game and message of "reconnect the controller" and without pressing anything the controller connects. It always messes up the flow. I tried putting batteries and use it without the cord, same thing happens. Dont think its the power source but im no expert.