Nova Pro - Backlight Inconsistencies



I have two Nova Pro units, both running identical FW and OS versions. One was purchased from Boox directly and the other was purchased from their page on Amazon.

The readers both function the same but differ wildly with regards to the backlight. When they are set to:
Warm: 30
Cool: 30
the lighting is nearly identical.

However, when the lighting is set to something more usable such as:
Warm: 8
Cool: 1
the Amazon unit looks warm and just bright enough to read in bed, while the Boox Direct unit looks like it has a blue led shining on it and is very dim and difficult to read.

Even more telling is when both units are set to:
Warm: 1
Cool: 0
the Amazon unit has a faint orange glow, perfect for a completely dark room and reading, while the Boox unit is nearly invisible with just this dark blue glow. Something that seems like it should not be present when “Cool” is turned off.

In order to get the Boox unit to match the Amazon unit, I must set them to
W: 15
C: 2

W : 3
C : 0

Is this common for these units to have such poor consistency and thereby such poor quality control? Can anyone think of what might be done to mitigate this?