UI blinks after being idle for one minute

Shifting from LibreElec to OSMC, I installed the latest image (2021-12) for Raspberry Pi 3 today.
When Kodi is idle for one minute, the entire UI goes blank/black, then back on again. non stop until I hit some key (up / down, doesn’t matter) that would take it out of idle.
After one minute, it will go back to it again.

It’s not fast flickering, rather more of flashing every few hundreds of milliseconds. I’m talking about this happening at the rate of you reading: black… back… black… back… black… back…

I have a photos slide show screensaver (happens with other screensaver too), that kicks in after 3 minutes, and the flickering continues while it does.

All power saving options are off when this happens.

I was using the Estuary skip.
After getting no where with the configurations, I downloaded and wrote the prev image (2021-11). After completing the initial language, etc. setup, without doing any operation and with the default OSMC skip, this started happening again.

This happens in 1920x1080p 60Hz and 50Hz as well.
This doesn’t happen when I lower the resolution to 1280x720p.

When playing a movie, this doesn’t happen.

Any ideas?

Try another HDMI cable.

This actually sort of helped.
“Sort of” because it still blinks but at a far lower rate. It blinks sporadically after 5/10/15/20/30/60 seconds. No real method to it. It’s just random, but it blinks.

My assumption is that OSMC is digitizing the HDMI connection in some way, and those blinks are failure to receive a response within a certain timeframe.
If this is the case, or something similar to this, then is there some config value to play with? E.g.: Increase some timeout value?

Update: Switching on the TV today, the blinking got back double time, blinking frantically, as much as 2-3 times a second. After using the remote it will get back to blinking randomly once in a while between 2-60 seconds, and in certain cases, get back to blinking frantically.
An OS update received today didn’t make any difference.
Not something I can cope with for now.

No idea what this is meant to mean.

OSMC and LE should be functionally similar.

Comparing config.txt from both devices would be interesting.

A description of your environment would also be useful.