DirectX 11 CreateSwapChainForHwnd fails with E_ACCESSDENIED

I am developing a directX 11 application. I am using IDXGIFactory2::CreateSwapChainForHwnd to create the swap chain after creating the DX11 device. The DX11 code is in an object that gets destroyed then re-created to render another video stream to the same HWND (window handle).

On the first run of the application IDXGIFactory2::CreateSwapChainForHwnd succeeds no problem. Then the application destroys the object with the DX11 code which destroys the DX11 device and swapchain etc. It goes to re-init the DX11 code again with the same HWND and this time IDXGIFactory2::CreateSwapChainForHwnd FAILS with E_ACCESSDENIED.

I have read the MSDN documentation that says there is a problem with differed destruction when changing swap chains. Here:

http://msdn.microsoft.com/en-us/library/windows/desktop/ff476425(v=vs.85).aspx#Defer_Issues_with_Flip

I tried to implement the suggested workaround to force the destruction of the objects:

D3D11Context->ClearState();
D3D11Context->Flush();

But IDXGIFactory2::CreateSwapChainForHwnd still returns E_ACCESSDENIED.

Does anyone have any insight as to why this could be happening? Thanks!