Can't get notifications.playsound to work

I can't get the notifications.playsound to work? I tested it out like so, below: 

using System;
using cAlgo.API;
using cAlgo.API.Indicators;
using cAlgo.Indicators;

namespace cAlgo.Robots
{
    [Robot]
    public class NewRobot : Robot
    {
        protected override void OnStart()
        {
            Notifications.PlaySound(@"C:\Users\lcespedes\Documents\cAlgo\Sources\Robots\test.mp3");
        }

        protected override void OnTick()
        {
            // Put your core logic here
        }

        protected override void OnStop()
        {
            // Put your deinitialization logic here
        }
    }
}