ffmpeg -i "input.mkv" -c:v copy -af "aformat=channel_layouts=5.1,pan=stereo|FL=FC+0.707*FL+0.707*BL|FR=FC+0.707*FR+0.707*BR" -c:a aac "output.mp4" Or simpler (ffmpeg default downmix, good enough):
ffmpeg -i "S03E05.mkv" -map 0:a:1 -c copy "commentary.aac" (soft subs only): rick and morty s03e05 ffmpeg
If you have a raw remux, a weird codec, or just want to compress this episode for your Plex/Jellyfin library, here’s a practical ffmpeg cheatsheet. ffmpeg -i "input