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Version 40 - Video playback becomes choppy when opening tabs

  • 5 replies
  • 2 have this problem
  • 15 views
  • Last reply by Phoxuponyou

crescent20
crescent20
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When playing video on any site (netflix, youtube) the video and sound become choppy and out of sync. I have tested this on two systems (one with NVIDIA GEForce video, one without) and it is the same problem on both. The problem is most noticeable when I open even a single other tab while watching a video. In FF39.x I did not have this problem at all. With FF40x, the problem is present on both systems. Any help would be appreciated. I do not believe this is a driver issue, since both systems use a different video adapter, and have the exact same problem.

When playing video on any site (netflix, youtube) the video and sound become choppy and out of sync. I have tested this on two systems (one with NVIDIA GEForce video, one without) and it is the same problem on both. The problem is most noticeable when I open even a single other tab while watching a video. In FF39.x I did not have this problem at all. With FF40x, the problem is present on both systems. Any help would be appreciated. I do not believe this is a driver issue, since both systems use a different video adapter, and have the exact same problem.

All Replies (5)

Phoxuponyou
Phoxuponyou
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Since Youtube now uses a HTML5 player, can you try Firefox in Safe Mode to see if plugins or some settings like hardware acceleration are the issue? Safe Mode troubleshooting instructions: https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode.

I had to refresh Firefox after some recent 40.x updates, apparently some settings got changed and my old profile became decrepit.

crescent20
crescent20 Question owner
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I forgot to mention in my original post that I had already tried Safe Mode, eliminating the possibility that it is one of my plugins. The issue was still present in Safe Mode , on both systems with different video. Thank you for your reply, and any further help by you or anyone else is appreciated.

Phoxuponyou
Phoxuponyou
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Did you try a Firefox Refresh then? https://support.mozilla.org/en-US/kb/refresh-firefox-reset-add-ons-and-settings.

It restored lost performance for me, as my updated 40.x started having issues that are now gone, thanks to a fresh profile and settings.

crescent20
crescent20 Question owner
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A refresh does not solve this issue, on either of my systems, one with NVIDIA graphics, one without. This is a browser-breaker for me, and if it is inherent to Firefox (which seems increasingly likely), I will be forced to change to another browser (which I do NOT want to do!).

Also, do I now have to rebuild that profile I refreshed from scratch, re-installing extensions?

Phoxuponyou
Phoxuponyou
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Well, that makes it abundantly clear it's not the hardware (at least not the gfx hardware) if it's the same issue on two different hardware platforms, yet other users can use Firefox fine (i.e. not a global bug). I can only think of software conflicts next (unless both hardware platforms use CPUs from the same family/with the same feature set). Any programs running that are shared by the two computers? Same OS?

Regarding Refresh, as it says first thing on the Refresh page: 'The refresh feature fixes many issues by restoring Firefox to its default state while saving your essential information like bookmarks, passwords, and open tabs. Note: Extensions and extension data are removed.'

Your old extension data - in case you didn't export it manually - will be in the old profile's folder (on desktop, if everything went according to plan).