noodles, my recollection from your original post on the TV was that you didn't smell anything and then you did. I also assume that you have been at your parents with that tv on in the past and didn't smell anything.
If that was the case then something in that TV has begun to fail and overheat, producing the smell. I've been around a bunch of LED TV's and none of them have smelled and as a matter of fact, none of the new LED TV's even get warm so there is really nothing to smell.
I would just pick one in your price range. Most name brand TV's are pretty cheap now (entry level)
I think the smell was there the whole time after whatever heated started to produce it because my sister stayed in there and until she left, she couldn't smell it either.
Last summer, we had Noodles in that room while the TV was on and she started doing some tail-bobbing while breathing, but she was having other health issues at the time, so, while I removed her from the room (in anticipation of taking her to the vet) I didn't assume that there was a connection between some sort of toxin within the room--I never went back in to investigate, and my nose would have been adjusted while in the room.
It wasn't until she had issues again (1 year later and in the same situation) that I put two and two together (plus, I noticed the scent this time, since I went back in there to open windows)... Note: I was opening windows all over the house as a last resort (not because I had noticed any fumes, but because the onset was sudden and severe)---I returned to the living room and detected a faint plastic/electronic scent (like a hot computer) but I wouldn't have gone back in there at all if t hadn't been to open the windows. My mom had been in and out of the room when the smell would have been present and until I pointed it out to her, she didn't notice it...SO it's really weird. My sister and I were in there watching movies, and the only reason we left was because the bird was acting weird.
I hope something is off with the TV, but at the same time, I have smelled this scent before in other people's homes and in schools...It is like the smell that comes from the vent of a hot computer....Does that make sense kind of? It isn't SUPER strong...It is electronic smelling and pretty mild...I'm wondering if it could be normal and if it normally just goes unnoticed.
I wonder if it isn't just the smell makes when it has been on for a few hours....We normally have the french doors open, but we shut them so all of the air was more concentrated...we also don't normally run it for 4 hours.
I found a lot of websites discussing off-gassing electronics and it would be awesome if I could find out whether this is normal or not-- I know it seems like something must have gone wrong, but the doors to that room are normally open (so any past smells would have been impossible to detect)...I am just kind of traumatized by all of it.
https://molekule.com/blog/what-you-should-know-about-vocs-and-off-gassing/
https://toxicfreefuture.org/pr-flame-retardants-tvs/
I know the links above are a bit....ermmm....."green" for my taste, but I do know that electronics can/do produce chemicals when operating properly.