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FireFox have two audio when play the mp4 with HTML5

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I am going to add video player to a existing website(written in GWT). so I add html5 video tag in the page and in Chrome and IE it works fine . but when I try firefox, the video can play , but it has two audio... and when I fast forward the video or pause the video, it doesn't impact one of the audio... seems it have another audio playing in the backgroud..but I can not find it....any one have ideas about this issue? I test in version 50 and 56... And I also tried disable all the plugins and extensions..but still have this issue....

I am going to add video player to a existing website(written in GWT). so I add html5 video tag in the page and in Chrome and IE it works fine . but when I try firefox, the video can play , but it has two audio... and when I fast forward the video or pause the video, it doesn't impact one of the audio... seems it have another audio playing in the backgroud..but I can not find it....any one have ideas about this issue? I test in version 50 and 56... And I also tried disable all the plugins and extensions..but still have this issue....

Modified by yangsh

All Replies (4)

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It has to do with coding. Firefox is looking too literally at the code. You might want to find a similar page of somebodies and see with a right click --> view page source what they have done as there are exemptions you can tell browsers to ignore ie: <--if Firefox ignore blah, blah blah -->

Or possibly you can run your code through the W3C.org (World Wide Web Consortium) that sets the standards and practises for both browsers and web pages. For code check HTML use : https://validator.w3.org/ For CSS use : https://jigsaw.w3.org/css-validator/ Correct coding equals better Google Ranking.

Please let us know if this solved your issue or if need further assistance.

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Pkshadow said

It has to do with coding. Firefox is looking too literally at the code. You might want to find a similar page of somebodies and see with a right click --> view page source what they have done as there are exemptions you can tell browsers to ignore ie: <--if Firefox ignore blah, blah blah --> Or possibly you can run your code through the W3C.org (World Wide Web Consortium) that sets the standards and practises for both browsers and web pages. For code check HTML use : https://validator.w3.org/ For CSS use : https://jigsaw.w3.org/css-validator/ Correct coding equals better Google Ranking. Please let us know if this solved your issue or if need further assistance.

hi Thanks for the replying

I am the first one to add video player to this application , so there's no other code I can refer . But I refer to w3c . but my application's doc type is HTML 4.01 Transitional , I am not sure if that will have impact on video playing

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Sounds that your code starts two players, possibly one hidden or both are on top of each other. You can use the builtin Inspector to see what code is generated.

You can right-click and select "Inspect Element" to open the builtin Inspector with this element selected.

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If the above suggestions do not resolve the issue, could you provide a link to a page demonstrating the problem?