Flickering main panel in a specific situation

Hi guys,

on my flight into the night this evening I've experienced a flickering on the whole main panel.

It has only occurred, when the flood lights were nearly turned off.

Here's a screenshot:

I think this effect is wanted & normal, but should only occur on the displays?!

I'm not 100% sure, but i believe, that I've seen this on the displays of the 737 NGX, too.

Maybe it's caused by my graphics card?

I mean, it's not a big problem, but it's a little bit annoying.

Here're my system specs:

AMD Radeon HD6850M (1GB)

i5 2450M (3,1 GHz)

8 GB RAM

ENB-Mod turned off

Any hints? Thanks, Sebi