from about 2 months ago on, sometimes, completly randomly my macbook will turn itself off with a strange noise. the noise is kinda like a *TZIK* then it turns off. it doesnt actually "turn" itself off, more so the screen goes blank straight away and its off with no warning and im not sure why its happen since after i updated the macbook to stop the buzzing problem (or mooing whatever) but not straight away so im not sure its that, but it might be somekind of overheating problem. its completly random when it turns off tho, cos alot of the time its under no stress what so ever, and is well ventilated on an iCurve. another thing im guessing is the battery, cos it seems to turn itself in bursts. like when it turns itself off, ill press the on button and most of the time itll come on, make the noise the cd drive makes at bootup normally, then *TZIK* its turned itself off again. any help?