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youtube HD videos lagging after 7.01

  • 7 replies
  • 44 have this problem
  • 3 views
  • Last reply by MagicMike

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1080p and 720p both worked fine in 7.0 and before that, but on 7.01 after having firefox open for about 10+ minutes they start to lag pretty bad, even with just that tab open. I thought it was add-ons at first but even in safe mode with addons disabled this happens after a short amount of time. The videos do not lag at first, only after some time has passed. In 7.0 and older I could leave firefox open for WEEKS and never have this issue. My ram usage is also not higher than normal, only at 500,000k right now...normally it goes between 250,000k and 1,000,000k with no problems.

Again, when viewing the troubleshoot information please keep in mind this issue is also happening in safe mode with no extensions on.

1080p and 720p both worked fine in 7.0 and before that, but on 7.01 after having firefox open for about 10+ minutes they start to lag pretty bad, even with just that tab open. I thought it was add-ons at first but even in safe mode with addons disabled this happens after a short amount of time. The videos do not lag at first, only after some time has passed. In 7.0 and older I could leave firefox open for WEEKS and never have this issue. My ram usage is also not higher than normal, only at 500,000k right now...normally it goes between 250,000k and 1,000,000k with no problems. Again, when viewing the troubleshoot information please keep in mind this issue is also happening in safe mode with no extensions on.

Modified by Kougeru

All Replies (7)

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The default of the pref network.http.max-connections has been increased from 30 to 256 in Firefox 6+ versions.

Try to decrease the value of the pref network.http.max-connections from 255 to a more modest setting of 30 as used in Firefox 3 versions.

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Didn't solve the issue unfortunately. I appreciate the reply though.

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


Which security software (firewall, anti-virus) do you have?

Make sure that it isn't blocking those Flash movies.

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"but even in safe mode with addons disabled this happens after a short amount of time."

I used safe mode and the problem still exists.

Microsoft Security Essentials is the anti-virus I use. it's not blocking flash. the videos play fine when not in full screen and no other website has issues (of course they don't have HD either..)

HD worked fine in 7.0.0 So I know it's not a problem on my system, I haven't changed anything.The problem started literally minutes after I updated to 7.0.1. That was the only change that happened.

Modified by Kougeru

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I don't know what 7.01 did exactly but I found out another interesting thing. Even if I leave my main window open with all it's tabs, a new window will play the videos smooth and normal. I assume it has something to do with my 5 tabs on my main window however this was NEVER a problem even since firefox 3ish. I've had up to 20 tabs opened for days on nearly all versions of firefox since 3 and never had this issue so 7.01 did something that makes it manage tabs technically worse than before..

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May i suggest using the new BETA Firefox,

I find doesnt have any problems with it for youtube.

Firefox Beta Link

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I was able to help this problem on Windows XP (where I mainly saw it) by disabling hardware acceleration.

Tools > Options > Advanced > General Tab > Uncheck "Use hardware acceleration when available"