Why did both of my tcl tvs have the backlights fail in the same room?

Why did both of my tcl tvs have the backlights fail in the same room?

I have 2 tcl roku tvs and 1 of them has had the backlights fail. Sound and picture still work. Swapped the tv with another 1 in the house and put it in the same outlet as the last tv. Now this one has the same exact problem. The backlights have gone out but the sound and picture still work with the flashlight test. Is there something wrong with the power outlet maybe that is causing this problem?

ANSWERS:

Have you tried this?