[Xbox 360] Image flickering in 720p; 1080i downscaled works fine!

Hi. I recently purchased a Samsung LN40 (LCD, 40", max output 720p ) and in the first three weeks, it was all rainbows and sunshine. Gayness aside, I don't know if the problem was always there and I was so excited that I couldn't see or it actually started recently, but I was playing Lost Odyssey the other day and noticed some weird image flickering. It's not flickering so to speak, its more like a large stripe on the screen (varying from 1 10th to 1 3rd of the screen size) changes its color hue and saturation levels for a few moments, than it changes back to how it was supposed to be. Now take this and picture several of these stripes on the screen at the same time and you got what I see. I had noticed this problem before, but it only happened when displaying still images against black backgrounds (such as load screens), as I don't remember being so many simultaneous stripes and the difference between the color they display and the color it was supposed to display was more subtle. I haven't tried to see if the problem existed in other disc games, but it happens as frequently on the Dashboard and Live Arcade games.

Now, the weird part. For some reason, I decided to set my Xbox 360 to output 1080i. My TV downscales 1080i to 720p and for my surprise, the stripes are gone! For many people, it would mean "problem solved" but not for me. What I wanna know is if is someone out there who has had a similar problem and if someone has any idea of what is going on, more especifically, where does the problem lie? Is it my TV? Maybe the component cable? The Xbox itself?

BTW, I noticed the same problem but in a way, waaaaaaay smaller scale when watching some DVD's the other day (480p), hardly noticiable, and haven't seen any indications of it when watching TV broadcast (crappy SD broadcast through composite cable, that is).

stick with 1080i problem solvedBoxcutters

As I said, it doesn't solve the problem for me, mainly for 2 reasons:

1) I put some good bucks on something and I want it to work as it is supposed to;

2) Doesn't downscaling 1080i to 720p makes on-screen renderization a little slower, thus adding a delay on in-game inputs? I mean, when playing something like Lost Odyssey, it doesn't make much difference, but won't gameplay be hurt by it when playing games like DMC or Geometry Wars? I still have to test that, so far I only tested GRAPHICAL differences between 720p and downscaled 1080i (and there was none although I experienced framerate gags twice in Lost Odyssey after switching to 1080i... sure, that could be the game engine's fault anyway).