@Override
    public void stop() {
        if (node != null) {
            node.stop();
            // Do not nullify the node for non-streaming nodes!
            if (fileName != null) {
                // Causes play() to reload the stream on the next playback
                node = null;
            }
        }
    }
For streaming music only. (May need to loop.)

@param ar for rendering audio (not null)
@param am the AssetManager for loading assets (not null)
@param fileName the path to the audio asset (not null)
jme3-niftygui/src/main/java/com/jme3/niftygui/SoundHandleJme.java