问如何在循环中停止setInterval

EN

var spans = document.querySelectorAll('span');
function getRandom() {
  return Math.random();
}
function scale(el){
  el.style.transform = 'scaleY(' + getRandom() +')';
}

var myInterval = null;

function startMusic (spans){
  var el = spans;
  for(var i = 0; i < el.length; i++){
      (function(i) {
            myInterval = setInterval(function(){
              scale(el[i]);
            }, 100);
      })(i);
    }  
}

function stopMusic (interval,els){
  
  clearInterval(interval);
  //console.log(els)
  
  for(var i = 0; i < els.length; i++){
    els[i].style.stransform = 'scaleY(0.05)'
     
    }
  
}



document.querySelector('.start').addEventListener('click', function(){
  startMusic(spans);
})

document.querySelector('.finish').addEventListener('click', function(){
  stopMusic(myInterval,spans);
})

body{
  margin: 0;
  
}

span{
  display: inline-block;
  width: 50px;
  height: 300px;
  background-color: #000;
  margin-right: 10px;
  transition: 0.1s linear;
  transform: scaleY(0.005);
  transform-origin: bottom;
}

.equalizer{
  position: absolute;
  top: 50%;
  left: 40%;
  transform: translate(-50%,-50%);
}

<div class="equalizer">
  <span></span>
  <span></span>
  <span></span>
  <span></span>
  <span></span>
</div>
<button class="start">START</button>
<button class="finish">FINISH</button>