عند الدخول في حلقه طويله لا استطيع التحكم في الفورم

السلام عليكم

اخواني عند الدخول في الحلقة التاليه

 For x As Integer = 0 To length

                        length2 = Un4seen.Bass.Bass.BASS_ChannelGetData(stream, data, length)

                    Next

اصبح غير قادر ع التحكم في الفورم حتى الخروج من الحلقه وهي حلقة طويلة جدا بالالاف .....

ارجوا ان تساعدوني في ايجاد الحل

هذا البرنامج كاملا

Public Class Form1
    Private StreamTHD As Thread
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        If TextBox1.Text.Trim = "" Then
            MsgBox("You must choose file", MsgBoxStyle.OkOnly, "ERROR")
        Else
            Application.DoEvents()
            Stream()
        End If
    End Sub

    Private Sub Stream()
        Dim fileName As String = "C:\test.mp3"
        Dim eror As String = Nothing

        If Un4seen.Bass.Bass.LoadMe() = False Then
            MsgBox("Error")
            Exit Sub
        End If

        Un4seen.Bass.Bass.BASS_Init(-1, 44100, BASSInit.BASS_DEVICE_DEFAULT, IntPtr.Zero, Nothing)

        Dim stream As Integer = Un4seen.Bass.Bass.BASS_StreamCreateFile(TextBox1.Text, 0, 0, BASSFlag.BASS_STREAM_DECODE)
        eror = Un4seen.Bass.Bass.BASS_ErrorGetCode

        If stream = 0 Then
            '' Stream = 0 error

            MsgBox("StreamCreatefileError" & Un4seen.Bass.Bass.BASS_ErrorGetCode)
        End If


        Dim lame As New EncoderLAME(stream)
        eror = Un4seen.Bass.Bass.BASS_ErrorGetCode


        lame.InputFile = Nothing   'STDIN
        eror = Un4seen.Bass.Bass.BASS_ErrorGetCode
        lame.OutputFile = Nothing   'STDOUT
        eror = Un4seen.Bass.Bass.BASS_ErrorGetCode
        lame.LAME_Bitrate = CInt(EncoderLAME.BITRATE.kbps_128)
        eror = Un4seen.Bass.Bass.BASS_ErrorGetCode
        lame.LAME_Mode = EncoderLAME.LAMEMode.Default
        eror = Un4seen.Bass.Bass.BASS_ErrorGetCode
        lame.LAME_TargetSampleRate = Int(EncoderLAME.SAMPLERATE.Hz_44100)
        eror = Un4seen.Bass.Bass.BASS_ErrorGetCode

        lame.LAME_Quality = EncoderLAME.LAMEQuality.Quality
        eror = Un4seen.Bass.Bass.BASS_ErrorGetCode
        'lame.Start(Nothing, IntPtr.Zero, False)
        'eror = Un4seen.Bass.Bass.BASS_ErrorGetCode
        If Not lame.Start(Nothing, IntPtr.Zero, False) Then
            MsgBox("LameStartError" & Un4seen.Bass.Bass.BASS_ErrorGetCode)

        End If



        Dim icecast As New ICEcast(lame)
        icecast.ServerAddress = "Salem-VAIO"
        icecast.ServerPort = 8001
        icecast.Username = "salem"
        icecast.Password = "b2006d"
        icecast.MountPoint = "/stream"

        icecast.StreamName = "2"
        icecast.StreamGenre = " Genre 2"
        icecast.PublicFlag = True
        icecast.SongTitle = "Test 2 Song"

        If icecast.Connect() Then
            If icecast.Login() Then
                If icecast.IsConnected() Then
                    Dim m_BroadCast As New BroadCast(icecast)

                    m_BroadCast.AutoReconnect = True
                    m_BroadCast.ReconnectTimeout = 5

                    Dim length As Integer = CInt(Un4seen.Bass.Bass.BASS_ChannelSeconds2Bytes(stream, 5))
                    Dim data(length) As Byte
                    Dim length2 As Integer
                    For x As Integer = 0 To length

                        length2 = Un4seen.Bass.Bass.BASS_ChannelGetData(stream, data, length)

                    Next
                    MsgBox("ok")
                End If
            End If

        Else
            MsgBox("Error")
        End If
        Return
    End Sub
End Sub
End Class