rendering currentTime after multiple pauses

gistfile1.js

function triggerPlaying() {
  if (!playing) {
    return;
  }

  var cur, x;
  var dur = as.buffer.duration;
  var diff = 0;

  var actualCurrentTime = ac.currentTime - firstPlay;

  if (lastPause > 0) {
    diff = lastPlay - lastPause;

    actualCurrentTime = actualCurrentTime - diff;
  }

  cur = (actualCurrentTime % 60) * 10;

  x = ((cur / dur) * 10).toFixed(3);

  waveProgress.style.width = x+"%";
  playCursor.style.left = x+"%";

  currentTimeBox.textContent = formatTime(ac.currentTime - lastPlay);
  remaining.textContent = formatTime((dur - lastPlay) - (ac.currentTime - lastPlay));


  if (parseInt(x) > 100) {
    playing = !playing;
    return;
  }
  webkitRequestAnimationFrame(triggerPlaying);
}