Maybe you have display scaling set to something other than 100% ??
www.tenforums.com/tutorials/5990-dpi-scaling-level-displays-change-windows-10-a.html
Other than that, I'm not really sure. The banding is implying some forced resolution which is not matching the aspect ratio of your window regions... I'm no expert in HKN, so I'm not sure what else to look for.