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youtube videos stuttering/lagging

  • 4 replies
  • 7 have this problem
  • 1 view
  • Last reply by Xtffox

Xtffox
Xtffox
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This might be asked before. Internet explorer 11 plays youtube videos without any lag or stuttering issue at all. but as I played the same video in FF, I immediately notice stutter. using FF ver64 on win8.1 64bit. Tried enble/disable HW acceleration, extensions, but no joy.

Is Mozilla aware of this?

This might be asked before. Internet explorer 11 plays youtube videos without any lag or stuttering issue at all. but as I played the same video in FF, I immediately notice stutter. using FF ver64 on win8.1 64bit. Tried enble/disable HW acceleration, extensions, but no joy. Is Mozilla aware of this?

Chosen solution

YouTube prefers a codec that can put heavy stress on your CPU called VP9. You can hide Firefox's ability to handle VP9 so that YouTube gives you H.264/MP4 instead and see whether that resolves it. This extension will do the job:

https://addons.mozilla.org/firefox/addon/h264ify/

Any difference?

Read this answer in context 👍 2

All Replies (4)

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 25 Contributor
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Chosen Solution

YouTube prefers a codec that can put heavy stress on your CPU called VP9. You can hide Firefox's ability to handle VP9 so that YouTube gives you H.264/MP4 instead and see whether that resolves it. This extension will do the job:

https://addons.mozilla.org/firefox/addon/h264ify/

Any difference?

Xtffox
Xtffox Question owner
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high end pc with no noticeable load on cpu but still suffer lag. it seems that was the cause. anyway thanks so much jscher2000

James
James
  • Top 25 Contributor
  • Moderator
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The new Firefox 64.0.2 update may help with the Youtube stuttering.

https://www.mozilla.org/firefox/64.0.2/releasenotes/

Xtffox
Xtffox Question owner
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finally they fixed it .....thanks James.