I hear double audio sound when youtube video is set to autoplay

I embedded a youtube video in the popup with autoplay=1 on page load.When i load the page i hear double audio sound of that video. However when i close the video popup, another audio is been played in the background. Any help would be greatly appreciated. Thanks.

My iframe code is :
<iframe src=”https://www.youtube.com/embed/hc7RymU_NJE?autoplay=1&rel=0&#8243; width=”860″ height=”515″ frameborder=”0″ allowfullscreen=”allowfullscreen”></iframe>

And I used this code in footer.php to get popup on page load :
if (is_home()) { popupwfb( $Popupwfb_group = “”, $Popupwfb_id = “” ); }

https://wordpress.org/plugins/popup-with-fancybox/