Help diagnosing slight flicker problem on Samsung plasma

[skatalite]

I was over at a friends' house yesterday, and he asked me to bring Incredible Hulk on Blu over so we could watch it. So, I do, and we begin watching it on his Samsung PN42A450 720p plasma, and it's looking great, but during the scene where Bruce Banner is learning breathing techniques, there was a slight flickering.

It can best be described as a flicker that occurred when natural light used in the film appeared on the screen. The screen dimmed itself, in a way, causing a flickering effect. It's not that the entire screen does a shifting of shade, just certain sections of the screen. Thing is, it only happened on that scene, and never again throughout the rest of the movie.

So, I run home, grab some more Blus to test out: Nothing happens on bright scenes in Dark Knight, everything is perfect on the opening scenes of No Country for Old Men. But then it happens in Juno, in the scene where Juno meets the parents-to-be at their house. It only happens when the characters walk in and are standing in the atrium, and during the short interview process.

Thinking perhaps it's a connection problem, we switch HDMI cables, and get the same results. I check his PS3 settings, all are good. Then, thinking it could just be a problem we have when we watch a Blu, we begin watching Superbad on HD cable. The same flickering effect happened when the two friends were waiting on McLovin to come out of the liquor store.

I'm thinking it could be something with his TV settings. He's got the following settings:

Movie mode
Cell light: 7
Contrast: 70
Brightness: 54
Sharpness: 25
Color: 50
Tint: G50/R50
Black Adjust: Off
Dynamic Contrast: Off
Gamma: -1
Color space: Auto
White balance: All 25
Flesh Tone: 0
Edge Enhancement: Off
Color tone: Warm 2
Size: Just Scan
Digital NR: Off
HDMI Black Level: Low
Film Mode: Off
Blue Only Mode: Off
Entertainment (Under Setup): Off
Energy Saving (Under Setup): Off


Any help would be appreciated. If there's an actual term for this, sorry for not using it, just haven't encountered this before. Or maybe this is just typical and we've yet to encounter it before?

Thanks, all!