When playing a file from the disk, AudioClip fails to play the sound when the path to the file contains a space character (the URL contains the %20 escaped sequence).
There is no sound being played and no error is outputed.

Sound files which do not contain spaces in their names are played Ok.

I haven't tested if this happens the same when accessing an audio file within an archive or from the web.

/*
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 * and open the template in the editor.
 */
package test;

import java.io.File;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;
import javafx.application.Application;
import javafx.builders.FlowPaneBuilder;
import javafx.collections.FXCollections;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.FlowPane;
import javafx.scene.media.AudioClip;
import javafx.stage.Stage;

/**
 *
 * @author fabriceb
 */
public class Main extends Application {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        Application.launch(Main.class, args);
    }

    @Override
    public void start(Stage primaryStage) {
        String[] files = {
            "C:\\Windows\\Media\\ding.wav", // Sound file from the disk.
            "file:/c:/Windows/Media/chord.wav", // Sound file from the disk (URL-style).
            "C:\\Windows\\Media\\Afternoon\\Windows Balloon.wav",
            "file:/C:/Windows/Media/Afternoon/Windows%20Balloon.wav",
        };
        List<Button> buttonList = new ArrayList<>(files.length);
        for (String file : files) {
            final String f = file;
            Button button = new Button(file);
            button.setOnAction(new EventHandler<ActionEvent>() {

                public void handle(ActionEvent event) {
                    play(f);
                }
            });
            buttonList.add(button);
        }
        FlowPane buttonPane = FlowPaneBuilder.create().id("buttonPane").hgap(5).vgap(5).children(FXCollections.observableArrayList(buttonList)).build();
        Scene scene = new Scene(buttonPane);
        primaryStage.setTitle("AudioClip + resources access test");
        primaryStage.setWidth(500);
        primaryStage.setHeight(500);
        primaryStage.setScene(scene);
        primaryStage.setVisible(true);
    }

    private void play(String resourcePath) {
        try {
            URL url = null;
            if (resourcePath.startsWith("http:") || resourcePath.startsWith("file:")) {
                url = new URL(resourcePath);
            } else {
                ClassLoader loader = Main.class.getClassLoader();
                url = loader.getResource(resourcePath);
            }
            if (url == null) {
                File file = new File(resourcePath);
                url = file.toURI().toURL();
            }
            AudioClip audioClip = new AudioClip(url.toExternalForm());
            audioClip.play();
        } catch (Throwable t) {
            t.printStackTrace();
        }
    }
}