I have an iMac running 10.5.8. I assume the built-in camera is that 5mm dot you see at the top center just above the screen. Other than doing something drastic like putting a piece of tape over it, is there a way I can know for sure that it is indeed turned off? I have no desire to use it anyway. Ditto for the mic. I don't want to end up like a student at a particular high school in the news not too long ago.