If you can still see the image in the background in dim light the inverter may be the problem. Much like a laptop though if it was me I would replace the lcd. You may be right in thinking that the connection may be loose. That is the first thing I check if I have that problem on a laptop.
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If you can still see the image in the background in dim light the inverter may be the problem. If it was me I would probably replace the LCD. You may be right in thinking that the connection may be loose. If it's not the cable then your LCD is slowly dying and it will continue to get worse. Your apple genius isn't much of a genius if all he did was a reinstall.
If you can still see the image in the background in dim light the inverter may be the problem. Much like a laptop though if it was me I would replace the lcd. You may be right in thinking that the connection may be loose. That is the first thing I check if I have that problem on a laptop.