Random glitch

Hi everyone ,
I'm currently working on an hologram shader with random time glitch effect. The thing is, I have the glitch effect appearing but everytime at the same time :/ Any help would be greatly appreciated ! Thanks.
I'm currently working on an hologram shader with random time glitch effect. The thing is, I have the glitch effect appearing but everytime at the same time :/ Any help would be greatly appreciated ! Thanks.