If you're experiencing playback errors while using Google Chrome as your browser, here's something you can try. There is currently a bug in Chrome on Windows, and this may fix your issue:
1) Open Chrome and type, chrome://flags
2) Scroll about a quarter of the way down the page and click 'Disable' in the 'Hardware-accelerated video decode' box. By default, this feature will already be on and the box/row will be gray; Disabling it will make the box/row white. You want it to be white.
3) Close and restart the browser.