grainy dim screen after flash sometimes

[Nwpayton]

Hey I flashed Odin samfail 2.5 then flashed fennec phone worked fine on samfail but after fennec every now and then I'm get a grainy screen almost like static and laggy for about a minute it sometimes passes, a screen lock sometimes fixes it or a reboot but it seems like an issue anyone know what it could be? I'm on Sprint SM-950U