Tryit Editor v1.8

Source Code:

<!DOCTYPE html> 
<html> 
<body> 

<button onclick="enableMute()" type="button">Mute sound</button>
<button onclick="disableMute()" type="button">Enable sound</button>
<button onclick="checkMute()" type="button">Check muted status</button>
<br> 
<video id="video1" controls="controls">
  <source src="mov_bbb.mp4" type="video/mp4">
  <source src="mov_bbb.ogg" type="video/ogg">
  Your browser does not support HTML5 video.
</video>

<script>
myVid=document.getElementById("video1");
function enableMute()
  { 
  myVid.muted=true;
  } 
function disableMute()
  { 
  myVid.muted=false;
  } 
function checkMute()
  { 
  alert(myVid.muted);
  } 
</script> 

<p>Video courtesy of <a href="http://www.bigbuckbunny.org/" target="_blank">Big Buck Bunny</a>.</p>

</body> 
</html>

Result:

W3Schools.com - Try it yourself

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