how come when ever i go to megavideo or southpark stuido and watch a video the video is always flickering?

Clear Cookies & Cache * https://support.mozilla.com/en-US/kb/Template:clearCookiesCache Clear the Network Cache * https://support.mozilla.com/en-US/kb/How%20to%20clear%20the%20cache#w_clear-the-cache Check and tell if its working.