How to count how many times an HTMLAudio has played?

Question

I'm trying to count how many times an HTML5 Audio object(audioPlayer) has played, by adding an 'ended' event, and using the played property which returns a Timesrange Object. Nevertheless, this approach only works
ok until the 1st complete listen, ie, when it ends I get a Timesrangeobject with all the partial listens. For further listens, it just "forgets" the 1st listen.

Here is my code

const audioPlayer = document.getElementById('soundPlayer');
audioPlayer.addEventListener(
    'ended',
    function() {
      const timesPlayed = audioPlayer.played;
      let totalTimePlayed = 0;
      for (let i = 0; i < timesPlayed.length; i += 1) {
        totalTimePlayed += timesPlayed.end(i) - timesPlayed.start(i);
      }
      const ratioPlayed = totalTimePlayed / audioPlayer.duration;
    },
    true
  ); 

A second question is: how do I force an ended event if the user leaves page while the audio is playing (ie, without having ended)? (This experiment is a multi-page webapp "survey" with an HTML5 Audio Element in each page, that the user listens to, then by pressing a button goes to the next page.

I'm trying to use the onbeforeunload, but I can't trigger the "ended" event.

function preventNavigatingAway() {
  window.onbeforeunload = function() {
    $('#soundPlayer').trigger('ended');
  };
}

Additional comment: I'm not sure if the order for which I'm calling the events is correct, so here is my full code:

function initAudio(audioPlayer) {

  audioPlayer.addEventListener(
    'ended',
    function() {
      const ratioPlayedInput = $("input:text[name='input-ratioPlayed']").val() || '0';
      let ratioPlayed = parseFloat(ratioPlayedInput);
      let timesPlayed = $("input:text[name='input-timesPlayed']").val();
      timesPlayed = parseInt(timesPlayed, 10) || 0;
      const currTimesPlayed = audioPlayer.played;
      let totalTimePlayed = 0;
      for (let i = 0; i < currTimesPlayed.length; i += 1) {
        totalTimePlayed += currTimesPlayed.end(i) - currTimesPlayed.start(i);
      }
      ratioPlayed += totalTimePlayed / audioPlayer.duration;
      ratioPlayed = parseFloat(ratioPlayed.toFixed(2));
      timesPlayed += currTimesPlayed.length;

      $("input:text[name='input-ratioPlayed']").val(ratioPlayed);
      $("input:text[name='input-timesPlayed']").val(timesPlayed);
    },
    true
  );
  return true;
}

function preventNavigatingAway() {
  console.log('preventNavigatingAway');
  window.onbeforeunload = function() {
    $('#soundPlayer').trigger('ended');
    console.log('in window.beforeunload()');
  };
}

document.addEventListener('DOMContentLoaded', function() {
  console.log('DOMContentLoaded!');
  const audioPlayer = document.getElementById('soundPlayer');
  initAudio(audioPlayer);
  preventNavigatingAway();
});