Problem displaying video in multiple windows with AVerMedia SDK

I have a problem trying to display video in more than one window at the same time using the AVerSetVideoWindowMultiple function, using only one window at a time it can switch to the new window but if I try to make it display in two or more windowsat the same time gives me this error :

Can't get the number of devices. AVer Capture SDK

I'm using a CL314H1 video capture card and the code is in C# with .NET 4

stopStreaming(_hCaptureDeviceGlobal_0, m_bIsStartStreaming_0);

            IntPtr[] hWndPreviewPictureBox = new IntPtr[2];

            hWndPreviewPictureBox[0] = btnHD0.Handle;
            hWndPreviewPictureBox[1] = BigPicture.Handle;

            AVerCapAPI.AVerSetVideoWindowMultiple(_hCaptureDeviceGlobal_0, hWndPreviewPictureBox, (uint)2);

            if (!m_bHadSetVideoRenderer)
                AVerCapAPI.AVerSetVideoRenderer(_hCaptureDeviceGlobal_0, (uint)VIDEORENDERER.VIDEORENDERER_EVR);

            GCHandle gchThis = GCHandle.Alloc(this);
            AVerCapAPI.AVerSetEventCallback(_hCaptureDeviceGlobal_0, m_NotifyEventCallback, 0, GCHandle.ToIntPtr(gchThis));

            if (AVerCapAPI.AVerStartStreaming(_hCaptureDeviceGlobal_0) != (int)ERRORCODE.CAP_EC_SUCCESS)
            {
                string palabra = "Can't get the number of devices. AVer Capture SDK";
                MessageBox.Show(palabra);
                return;
            }

            RECT RectClient = new RECT();
            RectClient.Left = 0;
            RectClient.Top = 0;
            RectClient.Right = BigPicture.Width;
            RectClient.Bottom = BigPicture.Height;
            AVerCapAPI.AVerSetVideoWindowPositionMultiple(_hCaptureDeviceGlobal_0, (uint)1, RectClient);

            AVerCapAPI.AVerSetVideoWindowPosition(_hCaptureDeviceGlobal_0, RectClient);`