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When watching video the video will slowdown while the audio is fine.

  • 4 replies
  • 2 have this problem
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  • Last reply by Bill

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When I'm watching a video the video portion will slow down several times while the audio is fine. I usually have to pause the video until it catches up to the audio to continue to watch it. I ran task manager in Win XP and noticed that when this problem occurs, Firefox is running at 98-100% of CPU usage. What might be causing this issue and how can I resolve it. Any help would be greatly appreciated.

Bill

When I'm watching a video the video portion will slow down several times while the audio is fine. I usually have to pause the video until it catches up to the audio to continue to watch it. I ran task manager in Win XP and noticed that when this problem occurs, Firefox is running at 98-100% of CPU usage. What might be causing this issue and how can I resolve it. Any help would be greatly appreciated. Bill

All Replies (4)

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Start Firefox in Safe Mode to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance).

To Enable SafeMode

  • You can open Firefox 4.0+ in Safe Mode by holding the Shift key when you open the Firefox desktop or Start menu shortcut.
  • Or open the Help menu and click on the Restart with Add-ons Disabled... menu item while Firefox is running.
  • Once you get the pop-up, just select "'Start in Safe Mode"

If it works in Safe Mode and in normal mode with all extensions (Tools > Add-ons > Extensions) disabled then try to find which extension is causing it by enabling one extension at a time until the problem reappears.

Close and restart Firefox after each change via "Firefox > Exit" (Windows: Firefox/File > Exit; Mac: "Firefox > Quit Firefox"; Linux: "Firefox/File > Quit")

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I started Firefox in safe mode but still have the issue with video running slow and task mgr is still showing Firefox running at 99%. Starting in safe mode seem to have no effect.

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Thank you for your help. It appears that creating a new profile solves the problem. So I guess my next question is why is my original profile causing this issue and how do I resolve the problem?