Last week all of a sudden my screen starts flickering when i play Videos such as from the Youtube app or on the browster. It flickers black then back to the video constantly. Please help it starts to aggrivate me.
Perhaps your signal is not quite good enough to support streaming video, perhaps your screen is failing. In any event, try entering recovery mode and wiping the system cache partition.
To wipe the system cache partition, you will have to enter recovery mode, where the option can be found. I doubt that the procedure is likely to be effective in your case, but it's possible. If you wish to try, follow this guide by Golfdriver97, who I trust will not mind if I refer you to it:
Let me say first, what I neglected to do earlier...Welcome to the forums.
Let me say secondly, I'm sorry that the problem persists.
You say that the fault shows itself when viewing YouTube videos. Does it occur if you watch videos or motion-picture effects....for example, games....via any app other than YouTube?
You may care to go into Settings, Apps, find the YouTube app, open it, and click on various options there...for example Uninstall Updates...but I don't know what the effect would be so I am not positively recommending it.
I hope that another member will be able to suggest a solution.