We have a 42 inch plasma TV that we bought in 2005. We have watched two Steeler Superbowl victories on it. It recently began to pop up the setup menu for no apparent reason. We would exit the setup menu and it would go away to just pop back minutes to seconds later. The longer the TV was on, the faster the menu came on. It really smelled like a software problem.
I looked for a firmware upgrade on the web. It is a Phillips TV and I just plugged in the model number and it produced the required files. I downloaded the file and copied it to a USB thumb drive. I plugged the drive into the TV and turned it on. The TV saw it and did the upgrade automatically.
The TV appears to be fixed. It was really quite a simple process. The key was recognizing it was a software problem.
I chatted with some my physicists friends after I fixed it and I asked if what they would have done. Turning the TV off, even pulling the plug was mentioned, but they did not come up with upgrading the firmware. I told them my solution and they thought they would have eventually have come up with the same solution.