[SOLVED] 820-3787 Amber tinted startup manager screen

[Revive]

Late 2013 15" Retina (DG)
The startup manager screen (from option being held down) is tinted a sort of pale pumpkin spice late color, after selecting the boot device the apple logo is white but the progress bar is tinted, once fully loaded everything returns to normal white balance.
Does this mean the MUX is slipping or something? any area I should focus on first?

 

[dukefawks]

I would suspect the LCD first. It is eDP interface so it works or it doesn't pretty much.

 

[Revive]

Cleared up with SMC and PRAM rest.
Solved thank you.