What do you mean by stuttering? It's not keeping the buffer filled for the player? It contains extraneous consonants?
Is this happening in the web interface? Android App? Jellyfin Media Player? Roku? Xbox? PS4? a Tesla dashboard?
Is Jellyfin running in a container? Linux? Windows? TempleOS?
But, to be serious, What have you tried so far? The answer is almost always some form of 'look at the logs' and 'use Google on any errors that occur' or if you're not rabidly anti-AI and have access to an agentic AI with web access you can go that route.