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MP4(h264 + aac) audio stream is not played

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Hi. I have a video file which playes in Chrome both video and audio fine.

When dropping it into Firefox (V 56.0.2) only the video part is played. The audio is disabled even at the interface level.

Now,here https://developer.mozilla.org/en-US/docs/Web/HTML/Supported_media_formats

I read this: " AAC is only supported in the MP4 container. To avoid patent issues, support for MPEG 4 and AAC is not built directly into Firefox. Instead it relies on support from the OS or hardware (the hardware also needs to be able to support the profile used to encode the video, in the case of MP4). Firefox supports these formats on the following platforms: Windows Vista+ since Firefox 22.0, Android since Firefox 20.0, Firefox OS since Firefox 15.0, Linux since Firefox 26.0 (relies on GStreamer codecs) and OS X 10.7 since Firefox 35.0. "

ShouldI understand from this that Firefox desktop browser on Windows 10 doesn't support AAC codec? If not,what is the alternative? Thanks.

Hi. I have a video file which playes in Chrome both video and audio fine. When dropping it into Firefox (V 56.0.2) only the video part is played. The audio is disabled even at the interface level. Now,here https://developer.mozilla.org/en-US/docs/Web/HTML/Supported_media_formats I read this: " AAC is only supported in the MP4 container. To avoid patent issues, support for MPEG 4 and AAC is not built directly into Firefox. Instead it relies on support from the OS or hardware (the hardware also needs to be able to support the profile used to encode the video, in the case of MP4). Firefox supports these formats on the following platforms: Windows Vista+ since Firefox 22.0, Android since Firefox 20.0, Firefox OS since Firefox 15.0, Linux since Firefox 26.0 (relies on GStreamer codecs) and OS X 10.7 since Firefox 35.0. " ShouldI understand from this that Firefox desktop browser on Windows 10 doesn't support AAC codec? If not,what is the alternative? Thanks.

All Replies (1)

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Firefox will use the codecs built into windows for playback, so if your missing AAC that means it's currently a windows problem.The last WIn10 update created a big mess with their drivers.

Go update your video card drivers directly from Intel/AMD/nVidia and restart.

then start Firefox and type "about:support" in the url bar then click "refresh firefox" on the top right. It should now be working,

By chance you have the "Windows 10 N" version of windows you will have to go download a special media pack from M$