I got one a few weeks ago and am loving it to death! My one problem is the remote won't switch between inputs. The source menu pops up when the button is pressed, but none of the other ones seem to actually swap between input options.
If it helps any, the television is also an ONN product, but seems to be from the mid-2000s going off the fact that the input labels can be set as "Wii" or "PS3."
I love that part of the ONN 4k, just scroll through the inputs, pause on the one you want and wait for it to change,. do not press anything.