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mp4 replay

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I have an mp4 (h264 AAC) video of 37MB which plays acceptably from my website in Safari, Chrome and Edge, but when played in Firefox (my default browser) the sound and picture synch is significantly seperated. When the video is compressed to 26MB it suffers some expected loss of sound quality but plays with near perfect lip synch. What is the issue with playback ?

I have an mp4 (h264 AAC) video of 37MB which plays acceptably from my website in Safari, Chrome and Edge, but when played in Firefox (my default browser) the sound and picture synch is significantly seperated. When the video is compressed to 26MB it suffers some expected loss of sound quality but plays with near perfect lip synch. What is the issue with playback ?

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Hard to help with something we cannot see. Can we try to replicate the issue? If so, provide a link.

Helpful?

Sual ver

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