Program time vs Music time

Question

I've been trying to make a game with music in it. I've been using a timer to keep track of the program's running time but I haven't been able to match up the music's playing time with my program's running time. Even when I get rid of almost all of my code it's still slower. Here's what I have for code.

    int timeInterval;
    int runningTime;
    DispatcherTimer drawTimer;
    public Game()
    {
        timeInterval = 100;
        drawTimer = new DispatcherTimer();
        drawTimer.Interval = TimeSpan.FromMilliseconds(timeInterval);
        drawTimer.Tick += dispatcherTimer_Tick;

    }
    protected override async void OnNavigatedTo(NavigationEventArgs e)
    {
        runningTime = 0;

        StorageFile file;
        StorageFolder InstallationFolder = Windows.ApplicationModel.Package.Current.InstalledLocation;
        string filePath = @"soundtrack.m4a";
        musicPlayer = new MediaElement();
        file = await InstallationFolder.GetFileAsync(filePath);
        var stream = await file.OpenAsync(Windows.Storage.FileAccessMode.Read);
        musicPlayer.SetSource(stream, file.ContentType);
        musicPlayer.Play();
        drawTimer.Start();
    }

    void dispatcherTimer_Tick(object sender, object e)
    {
        runningTime += timeInterval;

        if ((runningTime / 1000) % 10 == 0)
        {
            System.Diagnostics.Debug.WriteLine("Music: " + musicPlayer.Position.Seconds + "Running time: " + (runningTime / 1000) % 60);
        }
    }

Thanks for the help.

Edit: Here's some of the output

    Music: 0Running time: 0
    Music: 0Running time: 0
    Music: 0Running time: 0
    Music: 0Running time: 0
    Music: 0Running time: 0
    Music: 0Running time: 0
    Music: 0Running time: 0
    Music: 0Running time: 0
    Music: 0Running time: 0
    Music: 11Running time: 10
    Music: 11Running time: 10
    Music: 11Running time: 10
    Music: 11Running time: 10
    Music: 12Running time: 10
    Music: 12Running time: 10
    ...
    Music: 9Running time: 0
    Music: 10Running time: 0
    Music: 10Running time: 0
    Music: 10Running time: 0
    Music: 10Running time: 0
    Music: 10Running time: 0
    Music: 10Running time: 0
    Music: 10Running time: 0
    Music: 10Running time: 0
    Music: 10Running time: 0

Answer 1

DispatcherTimer.Interval is the minimum amount of time that will pass between Tick events. Usually it is more. You should use something like _startTime = DateTime.Now at the beginning and later do _runningTime = DateTime.Now - _startTime. You might also want to wait for musicPlayer.CurrentStateChanged until musicPlayer.CurrentState == MediaElementState.Playing before measuring the _startTime.

Then again - why not just get musicPlayer.Position as your _runningTime value?