I've been having issues getting videos to play without lagging. By lagging I mean... it sounds as if like a half second is stuck on repeat. I have problems with online movies (YouTube, videos on news sites, Vimeo - any and all videos) at any size player and with QuickTime and VLC. I thought it might just be low processing so I just upgraded my RAM to 4GBs. I know it's not my internet speed because my roommates can stream full screen videos fine. I've cleared my cache and cookies, moved all unnecessary files to an external hd, and I try quitting all background programs running through the Activity Monitor. I've also tried repairing disk permissions. Computer Specs: Mid-2007 MacBook - White 13" Version 10.6.8 Processor: 2.16 Ghz Intel Core 2 Duo Memory: 4 GB 667 MHz DDR2 SDRAM Hard Drive: Capacity - 319.73 GB Available - 160.51 GB Used - 159.21 GB Does anyone have any ideas on what I can do to maybe clean up my computer to make videos play smoothly? I'm out of ideas. Please let me know if you need any more information. Thank you!