I have an album thats a bit more than 200MB, converted to just an audio only M4a or MP4 its still under 80MB
Is that 120+MB all chaff or is there another way to prevent losing all muh damn wheat
CONSTRAINT/NON-CONSTRAINTS
FILE SIZE DOES NOT MATTER AT ALL TO ME. JUST TO BE CLEAR
MUST BE AN MP4 “video” file. I get that MP4 is a container or whatever but that is a hard constraint—Please respect that
M4A/AAC are not acceptable. It must be within the container that is MP4, non-negotiable


Haha this thread is full of folks explicitly ignoring what you said.
ffmpegshould be able to do this, since FLAC is one of the supported audio formats (although only since ISO/IEC 14496-14:2018 so your player might not support it). Read the manpage and do some trial and error.