When you change from basic to enhanced, you are establishing a RDP session to the VM through HyperV, and this allows to share local hardware as well as high DPI video settings. This is why the first you notice is the screen change.
In this case, I would be looking into performance issue, either try to reduce the screen resolution on the host / client as the GPU may not be able to feed both displays if the graphic generate data is too big to process. Also, you can start by updating BIOS, firmware and drivers, as well the Integration Services for the VM.
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