查看了DirectSound的MSDN文檔，才發現DirectSoundBuffer的Primary Buffer和Second Buffer還是有很大區別的，就像SetCurrentPosition函數不支持Primary Buffer。
這里是MSDN上的說明：
IDirectSoundBuffer8::SetCurrentPosition
IDirectSoundBuffer8::SetCurrentPosition
The SetCurrentPosition method sets the position of the play cursor, which is
the point at which the next byte of data is read from the buffer.
HRESULT SetCurrentPosition(
DWORD dwNewPosition
);
Parameters
- dwNewPosition
- Offset of the play cursor, in bytes, from the beginning of the buffer.
Return Values
If the method succeeds, the return value is DS_OK. If the method fails, the
return value may be one of the following error values:
Remarks
This method cannot be called on the primary buffer.
If the buffer is playing, the cursor immediately moves to the new position
and play continues from that point. If it is not playing, playback will begin
from the new position the next time the Play method is called.
相應代碼修改如下，用于建立新的DirectSoundBuffer8對象。
1 int CDSoundObject::CreateDSoundBuffer()
2 {
3 IDirectSoundBuffer* psbuffer = NULL;
4
5 DSBUFFERDESC desc;
6 memset(&desc, 0, sizeof(DSBUFFERDESC));
7 desc.dwSize = sizeof(DSBUFFERDESC);
8 desc.dwFlags = DSBCAPS_GLOBALFOCUS | DSBCAPS_CTRLVOLUME | DSBCAPS_CTRLPOSITIONNOTIFY | DSBCAPS_LOCSOFTWARE;
9 desc.dwBufferBytes = CDSoundObject::SIZE_DS_BUFFER;//header.data_size;
10 desc.lpwfxFormat = &_fmtWave;
11
12 if(_pDSBuffer != NULL)
13 _pDSBuffer->Release();
14
15 HRESULT hr = _pDS->CreateSoundBuffer(&desc, &psbuffer, NULL);
16 if(hr != DS_OK)
17 return -1;
18 hr = psbuffer->QueryInterface(IID_IDirectSoundBuffer8, (void**)&_pDSBuffer);
19 psbuffer->Release();
20 if(hr != DS_OK)
21 return -1;
22
23 return 0;
24 }