Me and my girls phones are having this same issue after upgrading to ZVH and flashing Your Mom Rom... not sure what the issue is... I have noticed it more while messing around in SetCpu... I disabled SetCpu and its doing it alot less now...
Actually just noticed... Setting both my girls phone and mine to max 768 (doesn't matter the min) The screen doesn't glitch... Also settings to max 691 (min doesn't matter) the screen glitches...