Backlight flicker/pulse…PWM or defect?

[AC Question]

I'm experiencing either a defect or an unfortunate feature on this tablet. I just took delivery of a new one, and while viewing any solid colors besides grey on the screen everything is fine (also no dead pixels), but I'm noticing what appears to be slight backlight flickering/pulsing whenever grey or light blue is shown on the screen. It seems to be PWM (pulse width modulation) of the leds, but I can't be certain it's a defect or just the unfortunate way these tablets' led screens are designed. It's a very subtle but consistent and annoying pulse, but it's definitely there. Can anyone confirm that PWM is what's going on with these tablets or if this is a defective screen. The screen doesn't pulse at all on any other colors solid or only partially filling the screen or otherwise.