Bounding box thickness

I randomly get this weird issue where the selection bounding box gets this super thick line which makes it hard to see what I’m doing. It’s totally random when it happens and sometimes it will even happen while I’m working. I’ll shut down the program and re-open it, but it’s a total gamble if it will just keep opening this way. I work at an animation studio where other animators have the same issue, but no one knows what causes it or how to fix it. I’ve included an image of the regular bounding box and the thick one for comparison.

I should also mention that I was on Windows 7 and never had this happen once. It’s only started since we upgraded to Windows 10. This is Toon Boom 14 by the way.