サイトにあったplayerの事について

こんばんは。
サイトにあったplayerを追加しました。

参考にあったサイト名：ZPlay VB.NET Class interface

http://libzplay.sourceforge.net/ZPLAYINTERFACE_VBNET.html
こちらのPlayerを追加したんですか、ちょっとお出すねしたい事があります。

教えてほしい事

リストボックスを選択すると再生したい

Imports MI_LIBZPLAY_AUDIO.libZPlay

Public Class Form1

    Private player As ZPlay
    Private LoadMode As Integer
    Private ReverseMode As Boolean
    Private Echo As Boolean
    Private VocalCut As Boolean = False
    Private SideCut As Boolean = False

    Private NextSong As Boolean = False

    Private FadeFinished As Boolean = False

    ' need this for managed stream
    Private fStream As System.IO.FileStream = Nothing
    Private br As System.IO.BinaryReader = Nothing
    Private BufferCounter As Integer

    Private CallbackFunc As TCallbackFunc

    Private BlockSlideLeft As Boolean = False
    Private BlockSlideRight As Boolean = False

    ''' <summary>
    ''' Text callback
    ''' </summary>
    ''' <param name="text"></param>
    ''' <remarks></remarks>
    ''' 
    Public Delegate Sub SetTextCallback(ByVal text As String)
'addfileopenfiledialog複数開けます。
Dim a As String()
    Dim file As String()
 Private Sub Button18_Click_1(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button18.Click
        LoadMode = 3
        OpenFileDialog1.FileName = ""
        OpenFileDialog1.Multiselect = True
        OpenFileDialog1.Title = "開くファイルを指定"
        OpenFileDialog1.Filter = "All Supported Files|*.mp3;*.mp2;*.mp1;*.ogg;*.oga;*.flac;*.wav;*.ac3;*.aac|Mp3 Files|*.mp3|Mp2 Files|*.mp2|Mp1 Files|*.mp1|Ogg Files|*.ogg|FLAC files|*.flac|Wav files|*.wav|AC-3|*.ac3|AAC|*.aac"
        OpenFileDialog1.FilterIndex = 1
        OpenFileDialog1.RestoreDirectory = True
        If OpenFileDialog1.ShowDialog() = DialogResult.OK Then
            file = OpenFileDialog1.SafeFileNames
            a = OpenFileDialog1.FileNames
            For b As Integer = 0 To file.Length - 1
                ListBox1.Items.Add(file(b))
            Next
            ListBox1.SelectedIndex = 0
            TextBox1.Text = System.IO.Path.GetFileName(ListBox1.SelectedItem)

        End If
    End Sub
    Private Sub OpenFileDialog1_FileOk(ByVal sender As Object, ByVal e As System.ComponentModel.CancelEventArgs) Handles OpenFileDialog1.FileOk
        OpenFileDialog1.Multiselect = True

        If LoadMode = 0 Then
            player.Close()
            If Not (player.OpenFile(OpenFileDialog1.FileName, TStreamFormat.sfAutodetect)) Then
                MessageBox.Show(player.GetError(), String.Empty, MessageBoxButtons.OK, MessageBoxIcon.Error)
                Exit Sub
            End If
        ElseIf LoadMode = 1 Then
            player.Close()

            Dim format As TStreamFormat = player.GetFileFormat(OpenFileDialog1.FileName)

            Dim fInfo As New System.IO.FileInfo(OpenFileDialog1.FileName)
            Dim numBytes As Long = fInfo.Length
            Dim fStream As New System.IO.FileStream(OpenFileDialog1.FileName, System.IO.FileMode.Open, System.IO.FileAccess.Read)
            Dim br As New System.IO.BinaryReader(fStream)
            Dim stream_data() As Byte = Nothing

            stream_data = br.ReadBytes(CInt(Fix(numBytes)))
            If Not (player.OpenStream(True, False, stream_data, CUInt(numBytes), format)) Then
                MessageBox.Show(player.GetError(), String.Empty, MessageBoxButtons.OK, MessageBoxIcon.Error)
            End If

            br.Close()
            fStream.Close()
        ElseIf LoadMode = 2 Then
            player.Close()

            Dim format As TStreamFormat = player.GetFileFormat(OpenFileDialog1.FileName)
            BufferCounter = 0

            Dim fInfo As New System.IO.FileInfo(OpenFileDialog1.FileName)
            Dim numBytes As UInteger = CUInt(fInfo.Length)
            If br IsNot Nothing Then
                br.Close()
            End If
            If fStream IsNot Nothing Then
                fStream.Close()
            End If

            br = Nothing
            fStream = Nothing

            fStream = New System.IO.FileStream(OpenFileDialog1.FileName, System.IO.FileMode.Open, System.IO.FileAccess.Read)
            br = New System.IO.BinaryReader(fStream)
            Dim stream_data() As Byte = Nothing
            Dim small_chunk As UInteger = 0
            small_chunk = CType(Math.Min(100000, numBytes), UInteger)
            ' read small chunk of data
            stream_data = br.ReadBytes(CInt(Fix(small_chunk)))
            ' open stream
            If Not (player.OpenStream(True, True, stream_data, CUInt(stream_data.Length), format)) Then
                MessageBox.Show(player.GetError(), String.Empty, MessageBoxButtons.OK, MessageBoxIcon.Error)
            End If

            ' read more data and push into stream
            stream_data = br.ReadBytes(CInt(Fix(small_chunk)))
            player.PushDataToStream(stream_data, CUInt(stream_data.Length))
'リストボックスとテキストボックス追加しました。
'リストボックスとテキストボックスに表示されます。（ボタン18）
        ElseIf LoadMode = 3 Then

        If Not (player.AddFile(OpenFileDialog1.FileName, TStreamFormat.sfAutodetect)) Then
                MessageBox.Show(player.GetError(), String.Empty, MessageBoxButtons.OK, MessageBoxIcon.Error)
                Exit Sub
            End If

        showinfo()
        player.StartPlayback()

    End Sub
'曲を選択、リスト選択可能※
  Dim IntSelectIndexPre As Integer = 0
    Private Sub ListBox1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles ListBox1.SelectedIndexChanged
        If ListBox1.SelectedItem <> "" Then
            TextBox1.Text = System.IO.Path.GetFileName(ListBox1.SelectedItem)
        End If
        If IntSelectIndexPre = ListBox1.SelectedIndex Then
            Exit Sub
        End If
        IntSelectIndexPre = ListBox1.SelectedIndex
        Timer1.Start()
        Timer2.Start()

    End Sub
’再生
 Private Sub Button2_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button2.Click
        player.StartPlayback()
    End Sub

    Private Sub Button3_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button3.Click
        player.PausePlayback()

    End Sub

    Private Sub Button4_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button4.Click
        player.ResumePlayback()
    End Sub

    Private Sub Button5_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button5.Click
        player.StopPlayback()
    End Sub
End Class

追加したコードの動作結果

開いたらリストボックスとテキストボックスに表示されました。
開いたファイルを選択すると曲を再生したいですが※の部分に

  Dim IntSelectIndexPre As Integer = 0
    Private Sub ListBox1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles ListBox1.SelectedIndexChanged
        If ListBox1.SelectedItem <> "" Then
            TextBox1.Text = System.IO.Path.GetFileName(ListBox1.SelectedItem)
        End If
        If IntSelectIndexPre = ListBox1.SelectedIndex Then
            Exit Sub
        End If
        IntSelectIndexPre = ListBox1.SelectedIndex
'※


        Timer1.Start()
        Timer2.Start()
            player.StartPlayback()

試した結果

※の部分

player.AddFile(a(ListBox1.SelectedIndex), TStreamFormat.sfAutodetect)

いろいろ試してやった所全くリストボックスを選択はされるんですが、選択後の
再生がしないので無理なんでしょうか？
お願いします。

開発バージョン

Vistual Studio2017 VB
サイトのプロジェクト使用しています。