Author Topic: Some M4A files not playing  (Read 125 times)

elan

  • Posts: 60
Some M4A files not playing
« on: 9 Nov '21 - 23:53 »
A customer reported these files not playing; BASS returns a BASS_ERROR_FILEFORM on Android and macOS (and possibly more places). They play fine in other players I tried, and ffmpeg inspection didn't turn up anything obvious I could see.

https://files.plexapp.com/elan/bad-file/2-06%20The%20One.m4a
https://files.plexapp.com/elan/bad-file/1-10%20MyMyMy.m4a

Please let me know if you have any questions!

Ian @ un4seen

  • Administrator
  • Posts: 23980
Re: Some M4A files not playing
« Reply #1 on: 10 Nov '21 - 13:14 »
Those 2 files are indeed failing on macOS here too. I guess there must be something about the files that Apple's MP4 parser/decoder doesn't like but I'm not sure what. The internal error code is kAudioFileUnspecifiedError (aka 'wht?'), which doesn't really tell us much. You can reproduce the problem with Apple's afconvert tool:

Code: [Select]
$ afconvert -f WAVE -d LEI16 "1-10 MyMyMy.m4a" test.wav
Error: Couldn't open input file ('wht?')

The files are working on the other platforms here though, including on Android when using either Android's codecs or the BASS_AAC add-on. Are you sure they aren't working on Android there? If so, what is the Android version, and are other MP4/M4A files working?

elan

  • Posts: 60
Re: Some M4A files not playing
« Reply #2 on: 10 Nov '21 - 22:07 »
Thanks for the quick reply!

I misspoke, the files aren't playable on iOS and macOS, which makes sense given they likely share the same parser. I'll let the user know they appear to be ... weirdly formatted.

elan

  • Posts: 60
Re: Some M4A files not playing
« Reply #3 on: 10 Nov '21 - 22:13 »
And by the way, I should have tried this before, but ffmpeg finds corruption.

[mov,mp4,m4a,3gp,3g2,mj2 @ 0x7fe70e808200] Packet corrupt (stream = 0, dts = 8670208).=56.9x
/Users/elan/Downloads/Albums for Elan/1-10 MyMyMy.m4a: corrupt input packet in stream 0
[aac @ 0x7fe6fe812400] Input buffer exhausted before END element found
Error while decoding stream #0:0: Invalid data found when processing input
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x7fe70e808200] stream 0, offset 0x300039: partial file
/Users/elan/Downloads/Albums for Elan/1-10 MyMyMy.m4a: Invalid data found when processing input