So I run this modpack. https://www.technicpack.net/modpack/project-evolution-main-course.1765540 and it has a 50 slot server but when I used audacity to convert some mp3 files to ogg and I put them on the server this error occured when players who didn't have the exact ogg files had. https://gist.github.com/P3rf3ctXZer0/4f119cd460e5a10901d2e8e41bc6fcaa it seems that for some reason there is nothing in place to push server files to client - if possible could you create a way for clients to recieve .ogg files through 1mb packets only when people play the music? This would effectively always make sure clients and servers match. I have a lot of time and the ability to test things if you need me to.

At time of writing this - this is the changelog https://github.com/P3rf3ctXZer0/Project-Evolution-Main-Course/releases/tag/project-evolution-main-course-10.0.0

This is your mod version.
Audio Cassettes v1.0 for 1.16.3
MCDJ v2.0 for 1.16.3

To @P3rf3ctXZer0, you could make use of Discord to transfer the music

You should speak with dev of Better Records - they figured out how to do it.

Theoretically it is possible to sync ogg files from server to client, but syncing music directly from minecraft server is probably dangerous thing. Previously i tried to make it possible but i face with a lot of bug.
I will not give up on this idea, but for now i can only recommend you to use mods that can play internet radio or don't change playlist on the server so often.