I first noticed the problem a month ago when the tv's volume went up by itself and wouldn't respond to anything from the remote for my tv or cable box remote. When I pressed the down volume on the tv control panel, the volume would go right back up. I was able to reset the tv and the problem went away. Then a couple of weeks ago, the picture would start to flash from black screen to picture, with the message "Check connections or power. The connections for RGBHv or yPrPb may be invalid. The flashes happened at random times during the day and sometimes within seconds of eachother.
I was thinking that the problem was with our cable box so I checked the connections and power cycled the box and the problem went away. Now this brings us to yesterday. The screen starts to flash again so I figured it was the cable box again, however, this time I left the tv on while I shut off the cable box. The screen still flashed but from black to blue(default screen color when there is no picture). The flashes happened multiple times within seconds of each other.
The controls from the remote was also not working and I was only able to turn off the tv from the control panel. When I turned the tv back on the volume indicator came up on the screen and moved up on its own. Pressing any button on the control panel or the tv did nothing so I had to unplug it. I waited 10 minutes, plugged it back in, and turned on the tv from the control panel (remotes still didn't work). The volume indicator came up but instead it was at its lowest setting. The volume would slide up a few notches then go back down. Pressing the device button would result in the highlighting box to "twitch" over multiple devices. Pressing the menu button resulted in the volume going up to its highest setting and staying there, regardless of anything else pushed. I decided to leave my tv unplugged overnight to see if that would help.
This morning I plugged the tv back in and the remotes still didn't work so I thought the same problems would occur. There was no flashing, and the volume came up at its lowest setting. I turned on the cable box and a picture came up. I pressed the volume on the control panel and it worked normally. I then tried the remotes and they started to work! I started to jump up and down for joy, but it was shortlived since I decided to test it and turned off the tv. Sure enough, I wasn't able to turn on the tv from either remote. I unplugged my tv again for 10 minutes and plugged it back in. The remotes still failed. I figured that this isn't really a bad thing since I change channels with the cable box anyway.
I left the tv on for about 15 minutes without any flashing or errors I could see. I decided to try the tv remote and for some reason its working. I can even turn on the tv from the remotes. I've been reading through the forums about the blinking green lights of death and the DM caps fix. I did the error code check and it returned a 12 (normal operation). At first I thought it was the DM caps, then I thought it was the control panel. I have no idea why my tv is suddenly working again and afraid that this won't be the last time. Sorry if this post is too long, I wanted to give as much info as possible. Any insight would be appreciated. Thanks in advance, Brian