I have recently bought a TV of RCA 55" model.
I started to play my PlayStation 3 games on HDMI connection.
It's my 2nd month playing & watching Roku on TV.
However just today while starting my regular video game on big screen TV, I noticed on half way of center of screen a horizontal crack on the division of top to bottom line shown vivedly while playing the game?? The crack line stayed there.
Naturally worried as I quickly discontinued to play games. I also disconnected the Roku box HDMI cable. I changed the setup setting to display in HDMI port changed from standard to graphic level??
I switched back to playing the game, the cracked line disappeared.
But I don't want to take chances?? Is it better to play video games back on the smaller TV?? Or shall I try again to play video games on big screen? Any help appreciated, thank you?

Link https://youtu.be/_g3a01o8d_Iote
The exact model number is RTU5540-C

Thank you for your crucial feedback.
Is it than possible to change video processing board?? I just don't want to hire a taxi to carry the unit all the way to replace. I was wondering if only a spare part could be replaced let's say I want invest in this unit?