Please tell me if you found out what the problem is, or if you found any solution about this problem. I've experienced this too on my macbook air, and i have no clue what to do, cause the garanty for free fix just stopped this christmas.
Does this mean this is far more severe than i actually thought it would be? Is it necessary to make a big deal out of it? couldnt it just be a software problem and not hardware? what did you do? thank you so much for your reply
Could be a hardware issue. I'd try re-installing OS X (first make a time machine backup first so you can re-install everything as it was) and see if the problem goes away. If not, get it exchanged asap if you still can.