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Download speed sporadic on Firefox only since upgrading to 11.

  • 3 replies
  • 4 have this problem
  • 16 views
  • Last reply by Htial

Htial
Htial
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Ever since upgrading to Firefox 11 I noticed streaming video was very laggy and buffering quite a bit. I ran a speedtest, and the download speed was all over the place as it was testing. My usual download speed is 14mbps, but when testing in Firefox was is hitting anywhere between 5-12 mbps. Usually averaging out to 5-6mbps. I ran the test in Google Chrome and the results were my usual 14mbps. I disabled then removed all of my add-ons and the issue continued. I reinstalled Firefox and still had the same issue.

I then downgraded to Firefox 3.6 and the problem went away, but when I upgraded to 11 again it came back. This issue only seems to be affecting Firefox as I continue to have normal download speeds on Chrome and on torrents.

Ever since upgrading to Firefox 11 I noticed streaming video was very laggy and buffering quite a bit. I ran a speedtest, and the download speed was all over the place as it was testing. My usual download speed is 14mbps, but when testing in Firefox was is hitting anywhere between 5-12 mbps. Usually averaging out to 5-6mbps. I ran the test in Google Chrome and the results were my usual 14mbps. I disabled then removed all of my add-ons and the issue continued. I reinstalled Firefox and still had the same issue. I then downgraded to Firefox 3.6 and the problem went away, but when I upgraded to 11 again it came back. This issue only seems to be affecting Firefox as I continue to have normal download speeds on Chrome and on torrents.

All Replies (3)

user633449
user633449
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If you create a clean testing profile, does it still happen there? https://support.mozilla.org/en-US/kb/Managing-profiles. This can help make sure your current profile isn't corrupted.

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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A possible cause is security software (firewall) that blocks or restricts Firefox or the plugin-container process without informing you, possibly after detecting changes (update) to the Firefox program.

Remove all rules for Firefox and the plugin-container from the permissions list in the firewall and let your firewall ask again for permission to get full unrestricted access to internet for Firefox and the plugin-container process and the updater process.

See:

Htial
Htial Question owner
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Did not fix the issue