I often play movies on an external Sony LCD via a Displayport-to-HDMI adapter. For the laptop display I have automatic brightness changing turned off, however in the setting for the Sony TV there is no checkbox. When watching a movie, the brightness shifts all over the place when a dark scene comes on. I've even tried wrapping the entire laptop up in a dark sheet (to block the light sensor) and it helps a bit but I'm worried about heat and it's a pretty ghetto (and not even 100% effective) solution. So my questions: 1. Is there a way to disable auto brightness changing for external displays? 2. Is it possible the TV is the one changing brightness? Don't think so because it doesn't otherwise do it.