<iframe width="100%" height="600" src="https://www.youtube.com/embed/aaa?autoplay=1&rel=0&showinfo=0&mute=1"  frameborder="0" allow="autoplay; encrypted-media" allowfullscreen></iframe>

<script>
var $iframe=$(this).find('iframe');
    if ($iframe.data('src')){ // only do it once per iframe
    $iframe.prop('src', $iframe.data('src')).data('src', false);
}
</script>