Same here. Was browsing the web with VLC playing in the background when the screen started to flicker a few days ago (29th of Marsh). It only got worse with time, and image ghosting started to appear. As if the screen was only refreshing one line of pixel on two.
The flicker now start as soon as the device is up. Always getting worse when getting warm. Most of the time, the flicker stop when I move the mouse cursor/touch the screen. But image ghosting persists when there.
I updated drivers, used diagnose tools, in pure waste of time. Starting the SP4 using Ubuntu live USB key confirm it is a hardware issue: the flicker is still happening, and image ghosting from the windows desktop would show on the startup screen (where it says try Ubuntu, install, etc.).
I always have been ultra cautious and thought I'd have problem with the power supply cables before the device itself!! Of course my SP4 is out of warranty, something like 2 years old. It is top of the range with smaller HDD (i7, 16GB ram, 256GB HDD), bought in view to work hard during travels... cost me an arm and a leg, and now is ripping my eyes out.
What an "out of warranty" scam... with that many users having the same issue, it is obviously a hardware conception problem. Microsoft better act fast on this one... hopefully.