Mine had this and together with the BridgeOS error I was getting and coil whine, I had to bring it back. Will wait till all these issues are solved. Judging from the questions and amount of information asked by the Apple support guys that contacted me, they still haven't figured out what is causing these issues. It has priority though considering they called me on a Sunday morning for some more information, so they are working hard on it to solve the issues. Whether you trust them with your money until they do is up to you of course.