Question TV repeatedly flashes black like it's loosing signal for a moment

[Opylom]

Hi!

I'm trying to run a 3 display setup. I have an RTX 2070, with 2 MSI 2k monitors connected with display ports, and an LG 4k tv via HDMI.
The two monitors are working perfectly, but the TV constantily flashes black for about 1 second every 15 seconds or so, loosing sound as well, like it drops signal for a moment.
I've tried multiple cables, but the problem persists regardless of wich port and what cable I'm using.
My setup is :
Intel core I5 6600k
MSI Gforce RTX 2070
16GB ddr4
2x MSI Optix MAG27CQ
1x LG 65UJ651V-ZA

 

[Ralston18]

What PSU do you have: make, model,wattage, age, condition?

LG TV: age, condition?

TV power source?

Do you have another known working TV or monitor to swap in for the flashing TV?

Try the TV on another known working computer. Determine if the problem follows the TV or stays with the current host PC/GPU.

 

[Opylom]

Thank you very much for the reply.

-I have a PSU from Thermaltake, 600W, I don't remember the exact model, but it's 4 years old. Condition should be good, but I'm not sure how to check it.

-the TV is 3 years old, works perfectly fine in itself, or with the chromecast 2.0 in all the HDMI slots. It's connected to a wall socket, EU standard 220V.

-I tried one of the monitors connected with the same cable, there was no flashing.