为何我的代码播放不了MID？

jimmymaster

如下：
Private Dx As New DirectX7

Private Ds As DirectSound
Private Dm As DirectMusicPerformance
Private Dl As DirectMusicLoader
Private DmSegment As DirectMusicSegment

Private w As WAVEFORMATEX

Private Sub Command1_Click()
  Set Ds = Dx.DirectSoundCreate(vbNullString)
  Ds.SetCooperativeLevel Me.hWnd, DSSCL_PRIORITY
   
  Set Dm = Dx.DirectMusicPerformanceCreate
  Dm.Init Ds, Me.hWnd
  Dm.SetPort 0, 0
  
  Set Dl = Dx.DirectMusicLoaderCreate
  Set DmSegment = Dl.LoadSegment("C:\back1.mid")
  Dm.PlaySegment DmSegment, 0, 0
End Sub

多谢了。
[em5]

Piscis

Dm.SetPort 0, 0这个好象不对，端口不可以为零（我用列举时，用0出错，从1开始才对）！如果使用默认端口，是-1。后面的通道组也好象不可以是零，是零的话，那不是无通道吗？至少是1吧？