Changing sample rate for microphone/speakers in Windows 7 - c++

Question

I need to change sample rate for microphone and speakers.
I know how to change volume levels for speakers and microphone using IMMDevice, but how can I set sample rate?
bool SoundDeviceControler::setVolume(EDataFlow dataFlow,float volume )
{
HRESULT hr = CoInitializeEx(NULL, COINIT_APARTMENTTHREADED);
if (FAILED(hr))
return false
IMMDeviceEnumerator *deviceEnumerator = NULL;
hr = CoCreateInstance( __uuidof(MMDeviceEnumerator), NULL, CLSCTX_INPROC_SERVER, IID_PPV_ARGS(&deviceEnumerator) );
if (FAILED(hr))
return false;
IMMDeviceCollection *deviceCollection = NULL;
hr = deviceEnumerator->EnumAudioEndpoints( dataFlow, DEVICE_STATE_ACTIVE | DEVICE_STATE_UNPLUGGED, &deviceCollection );
if (FAILED(hr))
return false;
UINT deviceCount;
hr = deviceCollection->GetCount(&deviceCount);
if (FAILED(hr))
return false;
IMMDevice *device = NULL;
for (UINT i = 0 ; i < deviceCount ; i += 1)
{
device = NULL;
hr = deviceCollection->Item(i, &device);
if (FAILED(hr))
return false;
IAudioEndpointVolume *endpointVolume = NULL;
hr = device->Activate( __uuidof(IAudioEndpointVolume), CLSCTX_INPROC_SERVER, NULL, reinterpret_cast<void **>(&endpointVolume) );
if (FAILED(hr))
retur false;
hr=endpointVolume->SetMasterVolumeLevelScalar(volume,NULL);
if (FAILED(hr))
return false;
hr=endpointVolume->SetMute(false,NULL);
if (FAILED(hr))
return false;
}
return true;
}