Bug with widget object Audio

The widget's beep is created with the following code:

function Beep(u) {
    this.url = u; //url of audio file
    this.stopped = false;
    this.audio = new Audio(this.url);
    this.start = function() {
this.stopped = false;
// -- deactivate on non-Windows; problems with sound
//if(navigator.platform.indexOf("Win") == -1) return;
//--
this.audio.loop(9999);
    }
    this.stop = function() {
this.stopped = true;
this.audio.stop(); 
    }
}

The Beep is created/started/stopped with this code:

// ============= Event handlers ==========================

// Execute the script on load
window.addEventListener('load', function(ev){
    //
    document.getElementById('closebutton').addEventListener('click', function(ev){	
        window.close();
    }, false);

    //////
    document.getElementById('stbutton').addEventListener('click', function(ev){
        toggleBeep(); 
    }, false);
    
    // --------- init 
    isBeeping = false;
    
    currentBeep=new Beep(beepfile);
}, false);

function toggleBeep() {    
    if (isBeeping) currentBeep.stop() 
    else currentBeep.start(); 
    isBeeping = !isBeeping;
}

The Beep is started and stopped by blue triangle button's clickhandler.

Reproducing the problem:

• Load the widget under Linux.
• Hit the blue triangle button to start/stop the looping sound.
• Under Windows the sound can be started and stopped and vice versa.
• Under Linux the sound can be started but not stopped.
  The sound loops forever until Opera is closed.

Click to load widget