Hello, and sorry you're having problems. We are now connected on this website- which saves you money over having a Tech come to your home, and in many cases we can fix the problem you're having. In other cases, these things do require additional parts to fix. But I can help you with that as well.
The first thing you should do is unplug all sources (Cable/SAT box, etc.), as well as the TV from power. Remove and reconnect all of your HDMI and AV Input cables making sure they are secure, and then plug everything back in as a reboot and see if the issue still occurs.
If so, then the next step you would try is to replace the HDMI cabling from the sources to the TV- these can be purchased for around $15 each from Radio Shack or Wal Mart, and are a very common cause of this problem.
If you're still having this intermittent flickering on the bottom half of the screen, and the ghosting on the top, then unfortunately this is a hardware failure occurring in the TV that requires service. There are no settings or adjustments that can fix this- and it ultimately does require service.
Most common internal issues that could cause this are failing Sustain/Buffer boards (part of the Plasma display processing- and typically a $350 repair), or possibly even the plasma display screen itself (the latter being non-repairable).
If you'd like you can use the link below to locate a tech in your area:
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