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Netflix is lagging (video/audio not matching) in Firefox but not in other browsers

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  • 1 has this problem
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  • Last reply by guigs

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When I open Netflix on Firefox, the audio and video start off in sync but in less than a minute the video falls far behind the audio. I tried it in Chrome and it worked fine, just not in Firefox. I also deleted the temporary Silverlight files (suggested on Netflix's support site: https://help.netflix.com/en/node/219) and of course I've tried restarting the browser many times, but it still doesn't work right. Help? I'm using Windows 8.1 on HP.

When I open Netflix on Firefox, the audio and video start off in sync but in less than a minute the video falls far behind the audio. I tried it in Chrome and it worked fine, just not in Firefox. I also deleted the temporary Silverlight files (suggested on Netflix's support site: https://help.netflix.com/en/node/219) and of course I've tried restarting the browser many times, but it still doesn't work right. Help? I'm using Windows 8.1 on HP.

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Please check your antivirus/firewall settings to make sure that silverlight xml application traffic is not flagged.

Are you using 64bit mode? http://www.microsoft.com/getsilverlig.../Default.aspx

Try to restart the browser after deleting the temporary files, it may also be the size of the cache. It is also possible to clear the cache for just netflix by going to about:permissions searching for netflix and clicking on "Forget this site"

I do not think that accleration would affect it, but to be sure please try:

Try disabling graphics hardware acceleration. Since this feature was added to Firefox, it has gradually improved, but there still are a few glitches.

You might need to restart Firefox in order for this to take effect, so save all work first (e.g., mail you are composing, online documents you're editing, etc.).

Then perform these steps:

  1. Open Firefox Options window (Preferences on Mac or Linux) as follows:
    • In Firefox 29.0 and above, click the menu button New Fx Menu and select Options for Windows or Preferences on Mac or Linux.
    • In Firefox 28.0 and previous versions, click the orange Firefox button at the top left, then select the "Options" button, or, if there is no Firefox button at the top, go to Tools > Options.
  2. In the Firefox Options (or Preferences) window, click the Advanced tab, then select General.
  3. In the settings list, you should find the Use hardware acceleration when available checkbox. Uncheck this checkbox.
  4. Now, restart Firefox and see if the problems persist.

Additionally, please check for updates for your graphics driver by following the steps mentioned in the following Knowledge base articles:

Did this fix your problems? Please report back to us!

Thank you.