It was cable. The one shipped with Vero works. Other (high speed) were causing issues with all 3 videos… Thx, really good tshooting step.
Edit: walking dog has 50% success rate. I just played another and went back to walking dog and it was OK…
Edit2: we need proper cable… https://www.spacehifi.com.au/hdmi-cable-guide
Edit3: I ordered HDMI 2.1 cable to definitely rule TV and Vero out. will update this thread once I get it.
Edit4: I got hdmi 2.1 ROLINE HDMI 8K (7680 x 4320) Ultra HD Cable + Ethernet, M/M, red, 2 m - SECOMP International AG and it still sometimes happen that tv switches to no signal with the sample videos. I guess it’s bit less chance to not to work than with bundled HDMI. But it looks ridiculous - like Kensington behind TV 
