I have a 2-3 year old 60" LG Plasma in the living room. It's been having blotchy issues for a while now, maybe 6 months or more. The issue is not the kind where it leaves behind the ghost image, it's just weird purplish-greenish splotches that show up on the middle area of the screen. Recently, they've also been showing up at the top and the ones in the middle were getting bigger.
My wife told me to buy a new one and stupid me had to search on the internet to see if anyone else had the issue. Sure enough, it's a known issue with LG Plasmas and someone posted a DIY fix for it.
TL;DR - There are some bad solder joints on one or 2 boards ( the zsus and ysus ) that you need to resolder. I had my buddy come over and take it off the wall with me, then we took it apart and sure enough, on the zsus board, some of the solder joints were definitely cracked.
I soldered the joints up and now the TV looks great. I know at least one person that we play Rocket League with has an LG Plasma but I can't remember who it is. This fix works for different LG Plasmas of different sizes.
Thanks to the Internet and a guy in the UK that goes by "Tom669", I spent $4 on solder instead of $2,500 on a new 70" TV.
This is a PSA for anyone else that has an LG Plasma and experiencing blotchiness. If _I_ can fix it, so can you.