My LG 52lg50-ua lost audio and video after x-box1 was plugged in. The back lights are still working, looks to have voltage at the marked terminals on the power board

SOURCE: Picture has been slowly getting darker and darker

how much out of warranty is it?
you should still get some support under the sale of goods act, in the UK, not quite sure anywhere else.
Take a look at this site if you are in the UK -
http://www.berr.gov.uk/whatwedo/consumers/fact-sheets/page38311.html
If you are in America then you will have to dooyour own search i'm afraid.
Hopefully this will help you.

When you spend this much on a tv it should last longer than 1 year, especially if someone is paying for it on installments.

SOURCE: i have a lg 52lg50 lcd tv,everytime i turn tv back

This memory loss issue sounds like a problem with the main board inside the TV. The channel memory should not erase after a power cycle.

You are probably loosing other custom programming like your Display and Audio settings. That is if you had modified something in these menus.

You may want to check to see if this is also happening by making a change in like the Display menu, and then turn the unit off and back on.

The TV has a one year warranty on parts and labor.

SOURCE: what is the factory password for 52lg50

The standard reset password should either be four zero's, '0000', or it will be what ever code you input when the promt comes on the screen. I hope this helps.

SOURCE: I have 47LH55-UA LG TV,

Sounds like a bad bulb.

SOURCE: i have an lg 52lg50

Hi, I've had that happen with TVs before, it tends to be caused by blown capacitors on the motherboard. It can be fixed however it's not something you could easily do on your own, you'd want to take the TV to a local repair shop, I've seen the repair range from $50 up to $250 or so in my experience.