Audio source is AC3 only and i do a copy video codec and convert ac3 to aac and then mux it, i tried to mp3 too same performance.
45 min series took me more than 3.5 hours
Anyone who has swap can confirm the conversion please
This is what i use its wrapped in shell script which when download completes looks at audio codec using mediainfo and converts if needed.
$this->bbcode_second_pass_code('', 'ffmpeg -i Input.avi -vcodec copy -acodec libmp3lame -ab 160k -ac 2 -vol 1024 output.avi')