I just recently got a new phone (LG Optimus S), and I keep running into this problem. I'll be watching a video on YouTube, the screen will glitch, and then all video that I try to play, whether its on YouTube or not, will be grainy and have the colors inverted. I've tried numerous things, like clearing my cache, force stopping all running programs, etc. The only fix I know of is restoring my phone to factory default settings. Does anyone know a fix that doesn't include me having to take the time to reinstall all of my previously installed apps/games? I'm pretty sure I'm not the only one that's had this problem, either. I've noticed a couple of threads where others have had the same problem, but with a different device.