Large Display: x by y w/ 24 bpp Graphics buffer visualized with neopixel string in zig-zag layout

Very interesting... just notice that it is color dependent... I draw a line with 0,0,8,3 in my 9 by 4 panel with each of these 4 colors:

 0:   1573095
 1:   7667850
 2:  15144960
 3:     51510

Colors 0: 1573095 and 3: 51510 do just fine... colors 1: 7667850 and 2: 15144960 fail (bleed w/ other 2 colors). Inspecting the buffer though: clean.

I'm looking for an explanation... There must be an easy answer. I will take a clip of the behavior...