>>183
やってみたけど駄目だ

[warning] No valid FFmpeg binary was found. See the --ffmpeg-ffmpeg option.
[stream.ffmpegmux][warning] Muxing streams is unsupported! Only a subset of the available streams can be returned!

Could not open stream: cannot use FFMPEG

ffmegが原因なのかな？入れてるしバージョンも最新なんだけど