MF SinkWriter memory problems

Question

I try to encode images of my desktop (1920x1080) to a video file using DXGI Desktop Duplication API and MF Sink Writer. My encoding thread looks like this:

#define RETURN_ON_BAD_HR(expr) \
{ \
    HRESULT _hr_ = (expr); \
    if (FAILED(_hr_)) { \
        qDebug() << "Error encountered with message from HRESULT: " << \
                    getMessageFromHR(_hr_); \
        MFShutdown(); \
        CoUninitialize(); \
        return; \
    } \
}

void DuplicationThread::run() {
    if (CoInitializeEx(NULL, COINIT_APARTMENTTHREADED) != S_OK) {
        qDebug() << "Failed to initialize COM.";
        return;
    }

    if (MFStartup(MF_VERSION) != S_OK) {
        qDebug() << "Failed to initialize Media Foundation.";
        CoUninitialize();
        return;
    }

    CComPtr<ID3D11Device> pDevice;
    RETURN_ON_BAD_HR(InitializeDx(&pDevice));

    CComPtr<IDXGIOutputDuplication> pDeskDupl;
    RETURN_ON_BAD_HR(InitiateDupl(pDevice, &pDeskDupl));

    CComPtr<IMFSinkWriter> pSinkWriter;
    DWORD streamIndex;
    RETURN_ON_BAD_HR(InitSinkWriter(&pSinkWriter, &streamIndex));

    LONGLONG rtStart = 0;

    while (!isInterruptionRequested()) {
        DXGI_OUTDUPL_FRAME_INFO frameInfo;
        CComPtr<IDXGIResource> pDesktopResource;
        RETURN_ON_BAD_HR(pDeskDupl->AcquireNextFrame(500, &frameInfo, &pDesktopResource));

        CComPtr<ID3D11Texture2D> pAcquiredDesktopImage;
        RETURN_ON_BAD_HR(pDesktopResource->QueryInterface(__uuidof(ID3D11Texture2D), reinterpret_cast<void **>(&pAcquiredDesktopImage)));

        CComPtr<IMFMediaBuffer> pMediaBuffer;
        RETURN_ON_BAD_HR(MFCreateDXGISurfaceBuffer(__uuidof(ID3D11Texture2D), pAcquiredDesktopImage, 0, FALSE, &pMediaBuffer));

        CComPtr<IMF2DBuffer> p2DBuffer;
        DWORD length;
        RETURN_ON_BAD_HR(pMediaBuffer->QueryInterface(__uuidof(IMF2DBuffer), reinterpret_cast<void **>(&p2DBuffer)));
        RETURN_ON_BAD_HR(p2DBuffer->GetContiguousLength(&length));
        RETURN_ON_BAD_HR(pMediaBuffer->SetCurrentLength(length));

        CComPtr<IMFSample> pSample;
        RETURN_ON_BAD_HR(MFCreateVideoSampleFromSurface(NULL, &pSample));
        RETURN_ON_BAD_HR(pSample->AddBuffer(pMediaBuffer));
        RETURN_ON_BAD_HR(pSample->SetSampleTime(rtStart));
        RETURN_ON_BAD_HR(pSample->SetSampleDuration(VIDEO_FRAME_DURATION));

        RETURN_ON_BAD_HR(pSinkWriter->WriteSample(streamIndex, pSample));
        RETURN_ON_BAD_HR(pDeskDupl->ReleaseFrame());
        rtStart += VIDEO_FRAME_DURATION;

        // successful iterations 
        static int count = 0;
        qDebug() << "count: " << count++;
    }

    RETURN_ON_BAD_HR(pSinkWriter->Finalize());

    MFShutdown();
    CoUninitialize();
}

Initialization routines are taken directly from Desktop Duplication Sample and Sink Writer Tutorial. Video format definition is also taken from the Sink Writer tutorial, with changes to frame resolution and VIDEO_INPUT_FORMAT = MFVideoFormat_ARGB32.

However, after going through this loop ~20 times (sometimes a bit more, sometimes a bit less), it fails on either mSinkWriter->WriteSample() or mDeskDupl->AcquireNextFrame() with the following HRESULT message:

The application made a call that is invalid. Either the parameters of the call or the state of some object was incorrect. Enable the D3D debug layer in order to see details via debug messages.

With D3D debug layer enabled, I see that my frames (I suppose those objects are my frames) are for some reason not released and just keep piling on:

D3D11 WARNING: Live Object at 0x0000006504FFC290, Refcount: 17. [ STATE_CREATION WARNING #0: UNKNOWN]

I'm fairly certain that HRESULT fails are coming from my GPU running out of memory (also confirmed by watching GPU memory usage via GPU-Z utility). However, I have no idea what causes this memory leak, because I'm releasing every resource that I'm allocating (SafeRelease implementation).

EDIT: Changed pointers to smart pointers and added macro definition.