I've just purchased a Thunderbolt display and have it hooked up to my MacBook Pro Early 2011 Model. Recently I've kept encountering a problem where the display will disconnect at seemingly random intervals. My hard drives plugged into the back will disconnect, and return unsafe ejection errors, and the screen will momentarily go back to my MacBook's built in display only. It only lasts for a few seconds before settling down but I can't understand why this is happening. Any ideas?