Crash when trimming a video that's on the repository

[AndroidDeveloperLB]

I've noticed that when trimming the video of the repository, it crashes:

intro.zip

The exception says :

E: Unsupported mime 'audio/ac3'
E: FATAL EXCEPTION: pool-1-thread-1
    Process: life.knowledge4.videocroppersample, PID: 26274
    java.lang.IllegalStateException: Failed to add the track to the muxer
        at android.media.MediaMuxer.nativeAddTrack(Native Method)
        at android.media.MediaMuxer.addTrack(MediaMuxer.java:626)

How come?

When making it trim without sound, it works fine, but then I don't have sound in the output video (of course)...

I wrote about this issue here too:
https://stackoverflow.com/q/54573454/878126

[AndroidDeveloperLB]

Oops this occurs because I've moved to Android framework's code.
However, I did this because this library can't use Uri instead of File, which I've reported here:
sannies/mp4parser#357