Default "backlight" flicker

I recently changed the casing on my kaiser and fired it up only to find I had a problem with back light flicker.

Except... I opened it and the LEDs that supply the light appear to be stable (no flickering).

This means the issue is with the LCD (I think).

any idea on how to fix it?

I'm running wm6.1 on 3.56.

I hope it isn't a circuit problem

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more obvious with darker backgrounds, the problem seems to be non-existent with a light background.

could be described as CRT flicker better

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on occasion, artefacts also appear.