I understand what you are saying, and your example is helpful.

I think perhaps I have been misunderstanding the nature of this
particular encoding error.  I had understood it to be an error in
encoding some audio at an arbitrary and random timecode.  What I now
speculate may be happening is that the error is at a fixed place near
the end of the file, perhaps in some kind of footer.  

Otherwise, I would expect some variability in when the file stops
playing, and it is very consistent.

I haven't been able to find adequate documentation of the ALAC format
yet to see how a file is structured, so I haven't really validated this
idea.

Some more information:

ffmpeg gives this error when transcoding one of the example files to
aac:
[alac @ 0x55794a5e1c40] invalid samples per frame: 0/s speed=79.3x
Error while decoding stream #0:0: Invalid data found when processing
input

Of note, I can transcode the original source flac with ffmpeg with no
issues, so the error seems to have been introduced when I used XLD to
transcode from FLAC to ALAC.

What's **really** interesting is that I can use ffmpeg to transcode the
original source FLAC and the XLD-transcoded (with error) ALAC both to
aac, and end up with *identical* files, despite the error thrown by
ffmpeg when transcoding the ALAC file.  That is to say, an md5 hash of
each outputted file is identical.  Both play to the very last note
outside of LMS, and I haven't yet tried them within LMS.

This suggests to me that the payload of the misencoded file is intact
and that the error is in a container structure.


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