This is really frustrating, when macbook was new it used to open so smoothly. But nowadays whenever I open it, a very annoying creaking voice is obtained. That kind of problem is seen in 2 macbooks by me myself, the same problem is in both of them. It sound so irritating, and moreover it sounds like something is broken inside the clams. But I cam assure u nothing is broken, its just it has loosened its smoothnes with time.