var fileName = @"D:\WindowsLogon.wav";

DevicesCollection sound_devices = new DevicesCollection();

Device sound_device_output = new Device(sound_devices[].DriverGuid);

sound_device_output.SetCooperativeLevel(new WindowInteropHelper(this).Handle, CooperativeLevel.Normal);     //设置设备协作级别

SecondaryBuffer secondary_buffer = new SecondaryBuffer(fileName, sound_device_output);                      //创建辅助缓冲区

secondary_buffer.Play(, BufferPlayFlags.Looping);                                                          //设置缓冲区为循环播放