YouTube: How to present embed video with sound unmuted

<iframe id ="videoPlayer" src="https://www.youtube.com/embed/uNRGWVJ10gQ?rel=0&autoplay=1&muted=0" width="560" height="315" frameborder="0" allowfullscreen></iframe>

I am doing this way but autoplay does not work . When i set muted=1 then autopaly works great . Any suggestion?

I tried to replace JS like below

var iframe = document.getElementById('videoPlayer');
            iframe.src = videoUrl + "&mute=1";
            iframe.setAttribute('allow', 'autoplay; encrypted-media');

but it still shows the same behaviour