Hello, I have a Dingoo A320 (black) with the latest firmware (1.2).

I have three vertical pixel-wide white bars that are burnt into the screen.  They seem to be appearing with every charge, even though I have been careful to not overcharge it.  Now that it's time to charge it again, I'm wondering if there's anything I should do differently?  Or do I have a defective screen?

Thank you very much in advance.