[FFmpeg-user] Could segments from one mpg have different audio offsets?

[Tom Horsley]

Sometimes I like to archive recorded programs from my TiVO,
downloading and tovodecoding the .mpg file, then using -ss
and -t to grab and transcode with libx264 the individual
chunks between the commercials.

Every so often, I'll find each individual chunk plays
flawlessly, but when I use the concat filter to stick
them all together, I wind up with audio sync problems
in the resulting concatenated video.

It just occurred to me that I've never checked to
see if the individual chunks all had the same
offset between video and audio streams.

Could that be what is going on? Might something
about the mpg file cause ffmpeg to generate results
where different offsets show up in separately
encoded chunks from the same source?

I'll have to be sure to check that the next time
I have an example with this problem, but I thought
I should ask to see if it is worth looking at,
or, for that matter, if someone else has a better
idea about how perfectly in sync segments could
wind up out of sync when I join them.