Can't get any screen output

Trying to run my Vero on an old Plasma TV (long story), it’s normally plugged into a 4k TV.

I cannot get it to output any display even the splash screen as far as I can tell.

Have tried:-
sudo fw_setenv hdmimode 720p50hzforce
sudo fw_setenv outputmode 720p50hzforce

and 1080p60hz etc to no avail.

Logs are here paste.osmc.tv/omobituner
Any bright ideas?

Have you tried a different input and/or HDMI cable?

Don’t use the force modes, it can stop your system booting. I suggest reverting that immediately.

I did, no change

2 different cables, 2 different HDMI ports on the TV

Have you checked the TV with another source?

Don’t really have anything else to hand I can plug into it.

If you can ssh into it, what happens if you tell it
echo 8bitnow | sudo tee /sys/class/amhdmitx/amhdmitx0/attr
?

I gave up in the end, it was a short term solution to a short term problem.
I was hoping it would just work.