[FFmpeg-user] First 10 seconds don't work well

[Resh]

Hello,

I noticed an "error" on ffmpeg.
When I use it to cut movies, or to extract parts of a movie, the video of the cut piece reproduces the first 10 seconds only audio, after which part audio and video synchronized. I did several tests on different types of files. I give an example to be more precise:
ffmpeg -i input.mp4 -ss 60 -to 600 -c copy output.mp4.

output.mp4 first 10 seconds is not visible, but the audio yes. After about 10 seconds of output.mp4, both are present. It's not dependent of output.mp4 lenght or duration.
How do you solve this problem?