The TV started doing this strange thing where the volume would turn down all by itself. Even after turning the volume back up, it would go back down again all by itself. TV works fine after several hours of watching, but then the volume on-screen display (OSD) will pop up randomly and sometimes the volume will change. After a while, the volume OSD pops up with increasing frequency, and the volume drops more and more until eventually it’s doing it all the time.
Ruled out the remote sending out random signals to the TV. Even took the batteries out to guarantee the remote wasn’t doing anything.
The control buttons on the side of the TV are capacitive touch buttons, so I thought maybe those had gone screwy. Opened up the TV and disconnected the control buttons, but it ended up having no effect. Still ended up with the same behaviour after a few hours of the TV being on.
At this point, I figure the problem is probably something heat related since the phantom volume changes don’t start happening until the TV’s been on a while. I’m not sure where else to go digging for the problem.
Looks like replacement control boards can be obtained from various sources for not a whole lot of money (definitely less than replacing the TV). Swapping out the control board would probably take care of the problem, unless of course the problem lies elsewhere.