M4A file issue inside Firefox

Question

I've tried using this audio file(http://files.parse.com/a2b14059-d5bd-481f-b639-933e80a1667f/480f7428-6067-4a6d-ab8b-b875a94c6b19-audioChat.m4a) in html but I'm having issues getting it to be recognized by Firefox 28. It just flashes and disappears. The interesting thing is if I have like 10-15 different audio tag links on one page, some of them would work while the rest would flash and disappear. By the way, I'm only having these trouble with FF, and not IE or Chrome.

This is one audio tag that does work:

<audio src="http://files.parse.com/a2b14059-d5bd-481f-b639-933e80a1667f/7ad7b994-1324-4ec1-9963-e4db20971745-audioChat.m4a" controls="controls" type="audio/mp4">Broken audio!!</audio>

This is one audio tags that doesn't work.

<audio src="http://files.parse.com/a2b14059-d5bd-481f-b639-933e80a1667f/480f7428-6067-4a6d-ab8b-b875a94c6b19-audioChat.m4a" controls="controls" type="audio/mp4">Broken audio!!</audio>

When I try to go to the file directly inside FF, it says the file is corrupt. On Chrome and IE it works fine.

I was just wondering, is the html malformed?

Could it be that FF28 doesn't fully support m4a yet?

https://developer.mozilla.org/en-US/docs/HTML/Supported_media_formats

I've checked in here but it does seem like it's full supported (mp4 at least).

I can't seem to tell if this is a FF media licensing issue or if the file is actually corrupted...

Answer 1

So I have attempted to compare the two files using ffprobe:

ffprobe -v quiet -print_format json -show_format -show_streams broken.m4a

The only major differences between the working.m4a and broken.m4a are:

• stream:
  • broken.m4a was created 16 years ago.
  • broken.m4a has no handler_name in it's tags.
• format:
  • broken.m4a has a much larger bit_rate.
  • broken.m4a has a different major_brand and compatible_brands in its tags

Here is the diff of the two outputs: