countspeed = 1;
clockStart = 0;

function times(n){
  if (n < 10) return "0" + n else return "" + n
}

clockTime = clockStart +countspeed*(time - inPoint);

if (clockTime < 0){
  minus = "-";
  clockTime = -clockTime;
}else{
  minus = "";
}

t = Math.floor(clockTime);
h = Math.floor(t/3600);
min = Math.floor((t%3600)/60);
sec = Math.floor(t%60);
ms = clockTime.toFixed(3).substr(-3);
minus + times(h) + ":" + times(min) + ":" + times(sec)