Indesign screen distortions when scrolling
I'm using InDesign CC 2018, and as I work between pages, scroll or zoom-in/out, screen distortions appear on the page. A sample image is attached.
In this example, the grey in the bottom right-half of the document isn't supposed to be there. It appears to be an artefact from the background. Changing pages or scrolling more will typically make the issue move to a different part of the page or disappear.
Any suggestions?

