Screen Flicker sad face

[NeilP]

I installed inexactly the same way
But my install worked first time, I had it up and running.

Then I thought I ought to updage /upgrade
I saw this page

Keeping your OSMC system up to date

How often is OSMC updated? OSMC receives a monthly update. This update brings bug fixes, stability improvements, performance improvements and new features. There are times when we need to deliver an update more urgently. In recent times we have seen some critical vulnerabilities, such as Heartbleed and Shellshock that needed addressing immediately. Kodi updates are made available as soon as they have been tested by the OSMC team to ensure that they deliver an experience to the standard you woul…

and did the

sudo apt-get update
sudo apt-get dist-upgrade

There was a message about needing to restart and relaunch X

So I restarted and the flashign sad face soon appeared.

I ahve tried bootign from the USB stick again, but not joy, stil the sad face.

The HDMI cable was working fine a few moments earlier, was ATV V 3.0? Video RGB HIgh

Where do i go from here?