I have recently installed Linux Mint 14 and youtube and other flash based videos are displaying lots of yellow and red specks. It doesn't matter which browser is being used either.
I've tried turning off hardware acceleration which didn't fix it.
Hardware is an old Lenovo Thinkpad X61 Onboard video is using the driver for Intel 965GM
** Update **
I just thought I'd try the HTML5 video trial on youtube. Instead of using flash it instead uses HTML5 to render the video stream. However, the problem remains only the speckles are now all a red colour.