53uwx10ba main lamps flashing off and on

I have a Hitachi 53UWX10BA which I got used. The previous owner said "when we turn it on, sometimes there is no picture but other times there is a picture. When it comes on, it looks great."

I took it home and see two problems.

1. The convergence needs to be adjusted. I assume it could be out of adjustment from moving it.

2. (Main problem) The picture tubes are flashing off and back on, all 3 at the same time. It happens sporadically with no rhythm to it and it is constantly flashing/blinking. If I try to use the setup menu, the flashing makes the menu disappear before I can select any menu options.

I have unplugged and replugged almost every connector in the whole tv to make sure its all connected properly and there is one that makes it stop flashing for a little while. From the front of the tv on the bottom left there is a silver box with a tiny button in front of it. Next to that silver box is a connector that comes from a hole in the wooden wall on the left. Looks like it goes behind the speaker but its not the speaker wire. If i wiggle this connector or press on it, the tv will stop flashing for a few minutes but starts flashing again at random.

When I do get it to stop blinking, the menu works fine, but pressing the Magic Focus button on the set does not bring up the adjusting screen.

I did not get a remote control with the tv so I assume I will have trouble adjusting the convergence even if I can fix the blinking problem.

Any ideas?