I now have the exact same problem, last time I ran Redream was a few month back and it was perfect, never had a problem with it. So today I try a few games and they all have screen glitches now, I've tried changing every option in the emu, grabbed the latest Redream release, no change. I'm still on Win 10, there was a update for it recently, dunno if that changed anything? Did you find a solution by any chance?