To retrieve and set the volume at which a buffer is played, your application can use the IDirectSoundBuffer::GetVolume and IDirectSoundBuffer::SetVolume methods. Setting the volume on the primary sound buffer changes the waveform-audio volume of the sound card.
Similarly, by calling the IDirectSoundBuffer::GetFrequency and IDirectSoundBuffer::SetFrequency methods, you can retrieve and set the frequency at which audio samples play. You cannot change the frequency of the primary buffer.
To retrieve and set the pan, you can call the IDirectSoundBuffer::GetPan and IDirectSoundBuffer::SetPan methods. You cannot change the pan of the primary buffer.
In order to use any of these controls, you must have set the appropriate flags when creating the buffer. See Buffer Control Options.