ffmpeg video cutting error: out of sync audio

Solution 1:

Because of Keyframes, combining -ss and -t options with -c copy, results in unsynchronizing video and/or imprecise duration.

Better is to have one cycle of decode/encode (although it results some quality loss) to get better timing . Cutting and converting at the same time is a better option and don't have above mentioned cons.

Solution 2:

I had a similar problem and it was solved in the following way, maybe it helps future readers.

ffmpeg -i test.mp4 -ss 2 -to 10 -c:v copy -c:a aac out.mp4

That is, I reencoded the audio. With this the audio was in sync. I don't think it makes a difference but note that my usecase needed the -to option instead of -t.