I installed my refurb U3100 and it was working great until I started changing the monitor settings (the knobs for horizontal/vertical sizes etc). Soon after doing this the screen started flickering and turned a weird orange color. After tapping for a while I got it back to the screen again, but it soon changed back into flickering again.
It seems like something's loose but maybe I'm missing something. I hope I dont have to ship this thing back

That would be a major pain. Anyway, any help would be appreciated! I have a friend over and I'd like to get it working so I can show him my arcade. Thank you!