zumo 400

[rusty700]

I have a zumo 400 been reliable for years, but since the last update it has had a couple of issues,

Fuel gauge does not work
occasionally top half of the screen inverts
any thing over 80 mph and it showed max speed of 256 mph
I could live with this.

But now I had an issue with the buttons on the screen not being in line when pressed, so did a screen calibration, but it would not read the position being pressed.

looked through a couple of sites and they recommended doing a hard reboot, so did this, I now have the set up screen showing language set up, press ok to accept, the button goes from green to yellow but does not move on to the next stage.

what could this be please? solution?

Thanks in advance