Sound doesn't play instantly...but wait for next operation to complete!!

I've a big interrogation concerning sound playback (WMP.lib)!
This code should play a sound, then compute...but it computes then play the sound!

Code:

---

Class MainWindow
    Dim writingPath As String = Environment.GetFolderPath(Environment.SpecialFolder.DesktopDirectory) & "\_UI Sounds\"
    Dim uiPlayer As New WMPLib.WindowsMediaPlayer
    Private Sub MainWindow_Loaded(sender As Object, e As System.Windows.RoutedEventArgs) Handles Me.Loaded
        RunTest()
    End Sub
    Private Sub RunTest()
        Debug.Print("Started!")
        uiPlayer.URL = writingPath & "son1.wav"
        uiPlayer.controls.play()
        '
        Dim a As Integer = 0
        For i As Integer = 0 To 999999999
            a = i
        Next
        Debug.Print("Done!")
    End Sub
End Class

---

I thought that I perhaps should run the sound in a thread to be sure that it's played by its own!?
But this gives the same result

Code:

---

Imports System.Threading
Class MainWindow
    Dim writingPath As String = Environment.GetFolderPath(Environment.SpecialFolder.DesktopDirectory) & "\_UI Sounds\"
    Dim uiPlayer As New WMPLib.WindowsMediaPlayer
    Dim uiThread As Thread = New Thread(AddressOf PlayFile)
    Private Sub MainWindow_Loaded(sender As Object, e As System.Windows.RoutedEventArgs) Handles Me.Loaded
        RunTest()
    End Sub
    Private Sub RunTest()
        uiThread = New Thread(AddressOf PlayFile)
        uiThread.Start()
        '
        Debug.Print("Started!")
        Dim a As Integer = 0
        For i As Integer = 0 To 999999999
            a = i
        Next
        Debug.Print("Done!")
    End Sub
    Private Sub PlayFile()
        uiPlayer.URL = writingPath & "son1.wav"
        uiPlayer.controls.play()
    End Sub
End Class

---

How should I please proceed to hear my sound 'instantly'?
What's my mistake?

Thanks for your help!!

Why are you using a busy loop that basically does nothing other than consume processor?

Well...I thought it was clear!! This is to illustrate a consuming process and keep the code simple to ask my question !!
Any idea?

No need for attitude... ;)

Anyways, there are other ways to play a sound, have a look at this FAQ :

http://forums.codeguru.com/showthrea...75#post1728375

Well, I had posted a simple code, hoping that it would be more clear for users to help me...but I'm afraid that I'd better post something very similar to my actual code..if I want the problem to be clearly exposed...and help you to try to help me ;-)

There's a sound class, called UISound:

Code:

---

Imports System.Threading
Public Class UISound
    Dim writingPath As String = Environment.GetFolderPath(Environment.SpecialFolder.DesktopDirectory) & "\_UI Sounds\"
    Public Shared WithEvents uiPlayer As New WMPLib.WindowsMediaPlayer
    Public Shared uiThread As Thread = New Thread(AddressOf ReceiveSound)
    Public Shared Sub ReceiveSound(ByVal url As String)
        uiThread = New Thread(AddressOf PlayFile)
        uiThread.Start(url)
    End Sub
    Public Shared Sub PlayFile(ByVal url As String)
        uiPlayer.URL = writingPath & url
        uiPlayer.controls.play()
    End Sub
End Class

---

The sound is called from a sub in the MainWindow...which itself fires other subs in cascade that involve a heavy compute time:

Code:

---

Sub one()
    UISound.ReceiveSound("sound1.wav")
    Dim a As Integer = 0
    For i As Integer = 0 To 999999999
        a = i
    Next
    Two()
End Sub
Sub two()
    Dim a As Integer = 0
    For i As Integer = 0 To 999999999
        a = i
    Next
    Three()
End Sub
Sub Three()
    Dim a As Integer = 0
    For i As Integer = 0 To 999999999
        a = i
    Next
End Sub

---

It appears that the sound is played after the whole "cascade" is runned, so after Sub Three() End.

Thanks for your help!!