Hello, just bought two copies of the monitor mentioned above. However on light blue and orange images, I notice very fine vertical lines (seems to be every 2nd pixel) that are a bit brighter and have a lighter tone. Both U2421E have it, one more than the other. I wouldn't have noticed on the better one if not for the worse one. It's barely noticeable so I'm wondering if this is something to be expected, faulty U2421E or easily fixable? The effect is similar to these two pictures here and here. Switching the GPU ports/ cables didn't change anything, the issue stayed with each U2421E. The connection is 2012 ThinkPad X230 -> docking station-> DP-> U2421E. With the Built-in diagnostics, I didn't see this effect. But there isn't a light shade available on there. On a side note, the OSD is poorly translated (I'm using German).