index.js

// display uploaded sound file
input.onchange = function(e){
  var sound = document.getElementById('sound');
  sound.src = URL.createObjectURL(this.files[0]);
  // not really needed in this exact case, but since it is really important in other cases,
  // don't forget to revoke the blobURI when you don't need it
  sound.onend = function(e) {
    URL.revokeObjectURL(this.src);
  }
}
// get name & comment values
const getNameComment = (name, comment) => {
	name = document.getElementsByClassName('name')[0].value;
	comment = document.getElementsByClassName('comment')[0].value;
	return [name, comment];
}
// get audio time stamp
const getTimeStamp = (audio, seconds, minutes, audioTimeStamp) => {
	audio = document.getElementsByClassName("audio")[0];
	seconds = parseInt(audio.currentTime % 60);
	minutes = parseInt((audio.currentTime / 60) % 60);
	audioTimeStamp = minutes + ':' + seconds;
	return audioTimeStamp;
}
// bind data to audio time stamp
const bindData = () => {
	[name, comment] = getNameComment();
	audioTimeStamp = getTimeStamp();
	let listItemData = document.createElement('p');
	listItemData.classList.add('listItemData');
	listItemData.innerText = `${name}: ${comment} @ ${audioTimeStamp}`;
	let listItem = document.createElement('li');
	listItem.classList.add('listItem');
	listItem.appendChild(listItemData);
	let commentList = document.getElementById('comments');
	commentList.appendChild(listItem);
};