Why does video on my Netlifx app (and others) show as pixelated?

I have an LG smart TV (55UF6800-UA). Oct 2015 build

About a month ago when watching Netflix, all video playback became pixelated. It doesn't matter which show or movie, it happens to all of them.

The still pictures on the apps are fine, but all video is colour pixelated.

This happens with other apps such as Plex, but not on Youtube.

There is no issue watching regular TV through the coax cable, connected from the antenna. The video is perfect.

There is no sound issue either.

Picture test also failed. Picture attached.

I have done a factory reset and checked the firmware and all is up to date. Also uninstalled and reinstalled the apps.

Any help is appreciated as LG could not provide any assistance.