LCD Backlight Fluctuation

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So I've been successfully using my MB64 for several months with out it falling apart (yay!), but I've recently noticed the LED backlight fluctuating every now and then. I can only notice it when viewed at an angle and it seems somewhat related to moving controls. It happens maybe every couple of minutes or so. I suspected it must be a power issue, maybe related to using a switching power supply, but it does it on my linear bench power supply as well (both far exceeding it's current requirements). 

Is this normal? It doesn't really bother me, I just want to make sure it's ok, and won't potentially damage anything.

Thanks in advance...