Font becomes grey and jagged when clicked and dragged across art-board

I'm on the latest version of Illustrator and every time I click and hold down on a text box to move it across the artboard, the font becomes grey and pixelates/becomes jagged. When I release it, it reverts back to black again. I'm also getting a strange, grey box to the right of the text block and the light-grey frame edges are very hard to see so it's difficult to work with any level of accuracy when designing. Screen shots attached for reference. Anybody else having these issues? 2021 worked fine - it seems to be problem after problem with 2022.