c# mediaplayer 播放问题

哪位大侠可以告诉我为什么程序this.axWindowsMediaPlayer1.Ctlcontrols.playItem(axWindowsMediaPlayer1.currentPlaylist.get_Item(s));前后2次令s=0。但播放的结果却不一样，前后相差一首歌？？？？
public void play(int s)
        {
            axWindowsMediaPlayer1.Ctlenabled = true;
            this.axWindowsMediaPlayer1.Ctlcontrols.playItem(axWindowsMediaPlayer1.currentPlaylist.get_Item(s));

        }