sleep

    Private Sub BackgroundWorker1_DoWork(sender As Object, e As System.ComponentModel.DoWorkEventArgs) Handles BackgroundWorker1.DoWork
        My.Computer.Audio.Play("C:\Users\fox\Downloads\31.wav",
    AudioPlayMode.WaitToComplete)
        MsgBox("hi") 'code to run after complete
    End Sub
    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        BackgroundWorker1.RunWorkerAsync()
        '     PlayBackgroundSoundFile()
    End Sub
    Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
        BackgroundWorker1.CancelAsync()
    End Sub
    Private Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click
        Timer1.Enabled = True
    End Sub
    Private Sub Timer1_Tick(sender As Object, e As EventArgs) Handles Timer1.Tick
        TextBox1.Text = "Timer Do Work" 'code work after timer start
        Timer1.Enabled = False
    End Sub