Just wanted to give a post-mortem on some serious 65833 issues I had. I originally bought my set from Vanns, but have had so many issues with it that I'm sending it back and have instead bought the Sony KDS-60A3000 at a local Best Buy so if I have further issues I can just return it locally.
I wanted to relate my experience here because I think it's a new (and hopefully isolated) issue with the set. The technician who helped me said he hadn't seen anything like it with the 833's before.
Original issues out of the box:
1) (I also bought an Onkyo TX-SR705 at the same time.) Hooked up HDMI components (PS3, HD Cable Box) through receiver, then sent HDMI out from receiver to TV. Upon first plugging HDMI into TV the Auto-Sense would recognize it, assign it the special, hidden "AVR" input name, and I could use it just fine. But if I turned the TV off or hit the "input" button to cycle to the next input, it would lose that connection and could not be restored except by unplugging the HDMI from the back of the TV and plugging it into a different port. If I plugged the PS3 and the Cable Box directly into the TV, I did not have this issue. I could turn the TV off and then on again and they'd still be there.
2) Excessive high-pitched whine coming from back of TV. Pretty typical. Not noticeable during an action scene or video game, but very evident during dialogue scenes. Tech thought it was probably the lamp as it sounded more electrical than mechanical.
3) Used DVI->HDMI cable to connect PC to TV. TV didn't detect the connection at all, let alone display a usable image.
Ok, so that was square one. I called Mitsubishi and they had me do a System Reset, which did nothing, and then unplug the TV, leave it for awhile, and plug it back in. Upon plugging it back in, the Timer light began to blink indefinitely and I was never able to turn the TV on again. Further System Resets and unpluggings/repluggings did nothing to alleviate the issue.
Tech talked to Mits, they sent him a new Main Board for the TV, and he came and installed it. You're probably fortunate to never have had your TV's chassis cracked, but I have now, and here's how it works: all of the analog inputs are on a secondary board which then plugs in vertically to the main board, which sits horizontally. The 3 HDMI inputs are on the main board. So: if the TV was the issue with my HDMI problem, one would assume that replacing the main board would fix it. All of that HDMI switching/detection happens on that board.
Here was the result:
* Timer Light issue fixed. Was now able to turn the TV back on.
* DVI->HDMI issue fixed. Was now able to use my PC on the TV.
* HDMI connection issue not fixed. This led me to believe that perhaps I had a bad receiver, something I'll have to investigate further when I pick up the Sony set tonight.
* High-pitched whine was not fixed (obviously) since that has nothing to do with the main board.
And, to add insult to injury, my picture now looks like absolute crap. Supposedly the tech did something which was supposed to auto-calibrate the TV, but it either didn't work or ... I don't even know what. But it looks HORRIBLE. I don't know the official term for it, but it's as if you set your computer's resolution to 8-bit color depth. Very few available colors, and no blending whatsoever. Everything chunky and pixelated. Grossness all around.
At this point the tech was at a loss, and he called Mits and they were at a loss too. Mits pointed the finger at Onkyo for the continuing HDMI issue (and, to add some possible credibility to this theory, a fellow in the Onkyo thread I use said he had issues in the past with HDMI handshaking and it was the source (i.e. the receiver) and not the TV that was the problem).
But since there is no real "light at the end of the tunnel" with all of this - just theories and possible fixes, I decided to send it back. With Heroes starting tonight and Halo 3 coming out tomorrow I don't have any time to be messing around for a month with trying to get my set working the way it should. It seems like this is either a very isolated case of a real lemon of a TV, or it's some kind of specific issue between these new 833 TVs and the new 705 Onkyo receivers. Only time will tell.
But I just wanted to put this out there so if you're having similar issues you can at least tell tech support you weren't the only one. And, whatever you do, don't agree to Mits's "unplug/replug" troubleshooting step. It kills your TV. :-P