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Baiscally the issue is that the youtube player is very sluggish on firefox (works perfect on chrome) i cleared cookies/update flash player help please.


-Youtube player itself (not so much the video or audio) lags horribly, for example when I try to scroll through a video the little preview frames feature that was implemented recentely those frames don't keep up with my cursor and it just feels sluggish -the initial load time of youtube videos is slow i can barely move my cursor around or click anything or even scroll down the page until about 40 seconds of waiting (during this time the video plays but the FPS are sluggish/choppy then it fixes itself sometimes) -ive tried clearing cookies/cache updating flash player etc -this issue is nonexistent with google chrome and IE

Additional System Details

Sites Affected


Installed Plug-ins

  • Shockwave Flash 11.4 r402
  • Nexon Game Controller
  • Next Generation Java Plug-in 10.7.2 for Mozilla browsers
  • NPRuntime Script Plug-in Library for Java(TM) Deploy
  • Google Update
  • npsitesafety
  • Adobe Shockwave for Director Netscape plug-in, version
  • Adobe PDF Plug-In For Firefox and Netscape 10.1.4
  • VLC media player Web Plugin 2.0.2
  • Pando Web Plugin
  • 5.1.10516.0
  • The QuickTime Plugin allows you to view a wide variety of multimedia content in Web pages. For more information, visit the QuickTime Web site.
  • iTunes Detector Plug-in
  • Adobe Shockwave for Director Netscape plug-in, version
  • The plug-in allows you to open and edit files using Microsoft Office applications
  • Office Authorization plug-in for NPAPI browsers
  • Unity Player 2.6.1f3


  • User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:15.0) Gecko/20100101 Firefox/15.0.1

More Information

some debug info from a video, not sure if this will help

Rezo 0 solutions 17 answers

First, I would uninstall and reinstall Firefox. Then, download the latest copy of Flash Player (Non-IE) from FileHippo. Install once re-installation of Firefox is complete. Also, try to use various websites that use streaming movie players to determine if it is in fact the browser, or youtube's video player.

  • Top 10 Contributor
  • Moderator
10762 solutions 96861 answers

You can check for problems caused by recent Flash updates and try these:

  • disable a possible RealPlayer Browser Record Plugin extension for Firefox and update the RealPlayer if installed
  • disable protected mode in Flash 11.3 and later
  • disable hardware acceleration in the Flash plugin