I'd try it with a shiny new under 10 buck Amazon Basics HDMI cable.
i just recently bought a LG 4k tv the model is a 55uf6450. i have owned the tv for less than 2 weeks. the issue i am having is that when im watching something through my PS4 in HDMI 1 which i believe is an HDMI 2.0 port everything will be going good and all of the sudden it will black out. i click the input button on the remote and then picture comes back perfect everything looks great. occasionally that black screen just comes on. the other thing is i watch mlb.tv and some green will flash at the bottom of the screen but this is rare not sure if this is because if the App or the TV. any information would be greatly appreciated.

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