i have 6 vmb6pbns running in my system, but with 2 of them i have some problems with the notification leds, not all leds light up. the first 3 are ok, but the next 3 are verry dark, they light up a verry little bit, but not like the first 3.
Don’t know in your particular case, but we have noticed an important spread on the applied leds. Most likely they are not binned.
Did you try with a different unit to check if the problem is related to VMB6PBN or the Niko buttons?