Hey, I have to tell you something: 10 Minutes ago I watched a video online and the LED illumination was about 40%. My room was dark and I tried to find something on my table, so I turned the illumination by holding the button F2 to maximum. After two seconds there was a weird sound, like a fan starts to spinning. The sound was becoming higher and I was afraid that something will get damaged, so I turned the light to the lower level and I could adjust the sound with the level of illumination. I hope you guys understand my desription! I can't reproduce the error, so some of you will say everything is good, but I am really afraid that my macbook has to say hello to a screwdriver!