My early 2011 MBP has recently been frustratingly sluggish whenever I watch high quality video (even 480p or less, occasionally). After a shot time viewing youtube videos I get very bad frame rate drops, fans going mad and CPU spikes. Pausing the video and allowing buffer time doesn't seem to have any discernible effect either. Here's an activity log of when it happens; Occasional when viewing youtube videos, my mouse speed also becomes super-sensitive for no apparent reason. It returns back to normal after closing the video down and waiting a few minutes. I've updated flash, reset SMC and PRAM tried HTML5 - nothing. Any ideas?