As far as I know the issue happened after using it a while, but I don't think I had watched anything with lights off for months after getting it, so there's now ay to 100% know. The seller insists it did not have a black level issue. For whatever that may be worth....
The reason I assume it's some physical issue is that if I turn contrast and brightness both to minimum levels, the black level is affected none at all. I would assume that no matter what other settings are changed, if those two can't get it looking black then something would have to be wrong. I certainly HOPE it's a settings issue, but there is another thread on here where a guy had the same exact problem and had it calibrated and the calibrator confirmed his contrast ratio was only one third the normal ratio, after calibration. This was three eyarsa go and he never got it fixed and sold it.
I've had a tough time getting a tv that didn't give me headaches, finally found this one and loved it other than the black levels, doesn't give me headaches, etc...., and now can't even get it fixed despite shelling out hundreds for an extended warranty.
There is only one authorized technician here apparently. At least, authorized by Pioneer.
The power supply, he had come out to check several issues I was having, including popping noises, and he did get some kind of error message related to the power supply. But it's even still popping, so that sure did no good. But as far as why I mentioned it here, some had claimed the power supply could cause it or bad voltage settings for it.
Also, this was manufactured in 2008, so before the batch where people had said worse black levels were more common. the technician claimed the panel itself passed all tests and was finel but the fact that he claims the black level looks oh so great proves he doesn't understand these tvs. And him saying it's "normal" for black to look gray! That is not normal on this set and I tried to get through to him that I tried a hx929, st50, st30 and all ahd MUCH blacker blacks. Heck, even a CCFL LCD I have has darker blacks, at elast on full black screens and black bars.
Thanks for the info. This is so depressing to find the right tv model for my needs and then it have this issue. If I knew a calibration would fix it, I would be very happy, but it's unlikely and would be $400+ down the drain on a tv I already wasted a ton on, if it can't improve much.