I've been having this issue for a few days now, though I'm not sure what's causing it.
Basically, I zoom out fast the trails of the object(s) I was focusing on seem to etch themselves into the background. As you can see from the screenshot, they stay there even with the 'Trails' option disabled.
I have tried clearing the trails, but nothing seems to work. Is anybody else having this issue? If so, how do you fix it?