You can check for problems caused by a recent Flash 11.3 update and possibly downgrade to Flash 11.2 or 10.3 (not sure how this works on XP) *https://support.mozilla.org/kb/flash-113-doesnt-load-video-firefox *https://support.mozilla.org/kb/flash-113-crashes You can try to clear the Flash local storage and settings. *Windows Control Panel > Flash Player > Storage: Local Storage Settings **Remove a specific domain: Local Storage Settings by site **Remove all domains: Delete All and Delete Data Flash Website Storage Settings panel: *http://www.macromedia.com/support/documentation/en/flashplayer/help/settings_manager07.html Global Storage Settings Panel: *http://www.macromedia.com/support/documentation/en/flashplayer/help/settings_manager03.html You can try to "disable the hardware acceleration" in the Flash Player. *http://helpx.adobe.com/flash-player/kb/video-playback-issues.html See also: *https://support.mozilla.org/kb/keep-flash-up-to-date-and-troubleshoot-problems Flash "Display settings" window: *http://www.macromedia.com/support/documentation/en/flashplayer/help/help01.html