Hi, This has nothing to do with the audio hiss issues, but another thing i found in my SR MBP. When theres any animation going on in the screen, theres this rapid clicking sound coming from somewhere, i still dont know where(it is around the fan vents the grey rubber strip below the silver "MacBook Pro"), but i know for sure it is not from the internal speakers. as i said, it is not audio related so muting or having music playing or connecting external speakers did/does/will not affect this problem. Things that will produce this rapid clicking sounds: Dashboard Exposé Front row Genie Minimise effect Scrolling a webpage Games Videos (anything that animates or moves) so i would say when there is any change in the display(when it is "active"), there will be this clicking sound. When the display is idle, it is silent. Even in slow motions (Shift+F12) the clicking is produced. Anyone else have this problem?