ADDITIONAL SYSTEM INFORMATION :
Ubuntu 22.10
OpenJFX 19

A DESCRIPTION OF THE PROBLEM :
When try to play a MP3 the MediaPlayer raises an exception: "com.sun.media.jfxmedia.MediaException: Could not create player!"

WAV files are working.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
see source code

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
no exception and MediaPlayer plays the MP3 - like WAV
ACTUAL -
exception

---------- BEGIN SOURCE ----------
package com.sample.MediaPlayerMP3Bug;

import java.net.URL;
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.layout.HBox;
import javafx.scene.media.Media;
import javafx.scene.media.MediaPlayer;
import javafx.stage.Stage;

public class App extends Application {

    private MediaPlayer mediaPlayer;

    @Override
    public void init() throws Exception {
//        var musicFile = "music.wav"; // works
        
        var musicFile = "music.mp3"; // fails
        
        URL fileUrl = getClass().getResource(musicFile);

        var media = new Media(fileUrl.toString());
        mediaPlayer = new MediaPlayer(media); // com.sun.media.jfxmedia.MediaException: Could not create player!
        mediaPlayer.play();
    }

    @Override
    public void start(Stage stage) {
        var root = new HBox(new Label("MediaPlayer-MP3-Bug"));
        stage.setScene(new Scene(root, 600, 400));
        stage.show();
    }

    public static void main(String[] args) {
        launch(args);
    }
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
using WAV - but it's not a viable workaround for real world applications

FREQUENCY : always