re: Sony TV / Vizio Sound bar Issue? Update

Quick update on this:

I factory reset the TV to no avail, and actually, as of yesterday, it seems that only one of the four HDMI ports is working. The input screen will show an icon next to HDMI inputs that have a device connected to them. I have devices connected in 2,3, and 4, but only HDMI 2 is showing the icon and giving any sort of activity, which is the DISH receiver. Even that one, as of yesterday, has no sound, and every 5 seconds the picture blinks black for about 2 seconds.

I moved the dish receiver HDMI cable to the other HDMI ports and it just shows no signal as if nothing is plugged in to them.

I turned on the blu ray player and switched to that HDMI input, and the screen is black with no activity.

I did all of this trouble shooting before factory resetting the tv last night, and the factory reset didn't change the issues at all.

The internal apps on the TV work great still, so I'm researching the prospect of replacing the main board on the TV. I'd hate to not give this thing some love as it's been an incredible TV until lately. It also seems like other than Sony's master class they still haven't produced a TV as good as this one., other than the recent X95K. It looks like a board is around $200. My brother is tech-handy and I'm a handy person as well. Is replacing the main board as easy as it seems or is there more to consider? It seems to be just disconnecting some ribbons and connections and unscrewing.

Never replaced a tv circuit board before, so any advice is appreciated.