Thread hs;
    hs = new Thread(()=>Playsound(sound));


while (bstate==-1)
{
    t = Int16.Parse(bpm.Text);
    t = 60000 / t;

    hs.Start();

    cajas[compas-1].Fill = new SolidColorBrush(Colors.White);
    cajas[0].Fill = new SolidColorBrush(Colors.Red);
    await Task.Delay(t);

    for (int k = 1; k < compas-1; k++)
    {


        hs.Start();
        cajas[k-1].Fill = new SolidColorBrush(Colors.White);
        cajas[k].Fill = new SolidColorBrush(Colors.Black);
        await Task.Delay(t);
    }

    hs.Start();

    cajas[compas - 2].Fill = new SolidColorBrush(Colors.White);
    cajas[compas - 1].Fill = new SolidColorBrush(Colors.Black);
    await Task.Delay(t);

}