Hej,

använder följande klass för att spela upp bland annat .wav filer,

    Public Class SoundClass
        Declare Auto Function PlaySound Lib "winmm.dll" (ByVal name As String, ByVal hmod As Integer, ByVal flags As Integer) As Integer
        ' name specifies the sound file when the SND_FILENAME flag is set.
        ' hmod specifies an executable file handle.
        ' hmod must be Nothing if the SND_RESOURCE flag is not set.
        ' flags specifies which flags are set. 

        ' The PlaySound documentation lists all valid flags.
        Public Const SND_SYNC = &H0          ' play synchronously
        Public Const SND_ASYNC = &H1         ' play asynchronously
        Public Const SND_FILENAME = &H20000  ' name is file name
        Public Const SND_RESOURCE = &H40004  ' name is resource name or atom

        Public Sub PlaySoundFile(ByVal filename As String)
            ' Plays a sound from filename.
            PlaySound(filename, Nothing, SND_FILENAME Or SND_ASYNC)
        End Sub
    End Class

    'Användning
    'Dim tpmPlay As New SoundClass
    'tpmPlay.PlaySoundFile("ljud.wav")

Nej, den kan inte spela upp mp3. Den är avsed för wav filer.

Vilken klass ska jag använda då?

Borde kunna gå med managed directX.
Kanske...