Suddenly random effects on all my clips - what happened?

[benjamin Philipp]

I'm not sure what I did, but somewhere between inserting a title card and scrolling back to the beginning of the timeline, something happened.
Now all of the clips on my timeline appear to have some video effect on it:
Either the colors are effed up (weird mix), or the picture is flipped upside-down, flickery and in grayscale.

There is nothing out of the ordinary in the effects panel for the clips

Does this seem familiar to anybody?
Any idea what happened and how I can undo it?

Thank you guys

[Ann Bens]

Green or purple streaks appear in the Source and Program monitors

[benjamin Philipp]

Huh...

I restarted Premiere and everything was back to normal.

That means I can't provide any more useful insight into the issue, but it seems at least that the problem was only a momentary glitch.

Good luck to everybody else out there having the same problem