title: The FFmpeg-generated video mute after seeking it forward
body: <p>The video mutes after seeking it forward. It was created with FFmpeg. When I play it normally (without seeking it), the audio played. I am a Linux user and test it with <a href="https://en.wikipedia.org/wiki/VLC_media_player" rel="nofollow noreferrer">VLC media player</a> and <a href="https://en.wikipedia.org/wiki/Mpv_(media_player)" rel="nofollow noreferrer">mpv</a>.</p>
  <p>I generated it with this:</p>
  <pre><code>ffmpeg  -i video.flv -i audio1.flv -i audio2.flv -i audio3.flv -i audio4.flv -i audio5.flv  -i audio6.flv  -i audio7.flv  -i audio8.flv  \
  -filter_complex &quot;\
  [0:v]tpad=start_duration=29.429[v];\
  [1:a]adelay=3654.0[a1];\
  [2:a]adelay=53563.0[a2];\
  [3:a]adelay=1148851.0[a3];\
  [4:a]adelay=1313774.0[a4];\
  [5:a]adelay=1373197.0[a5];\
  [6:a]adelay=2061735.0[a6];\
  [7:a]adelay=2736617.0[a7];\
  [8:a]adelay=3387278.0[a8];\
  [a1][a2][a3][a4][a5][a6][a7][a8]amix=inputs=8[a]&quot;\
   -map &quot;[v]&quot;  -map &quot;[a]&quot;  -c:v libx264 -crf 23 -c:a mp3 -s 500x500 -shortest ./output.flv
  </code></pre>
  <p><code>[1:a]</code> and <code>[5:a]</code> is a main audio (other audio have small duration). If I seek after 1373197.0 ms, the video has been muted (when <code>[5:a]</code> must be played).</p>