monitor sometimes powers on dimmer with a tan overtone

[rockin_rick]

I've got two relatively new ViewSonic G70f monitors that I use daily.  Every once in a great while (say maybe five times in two years of daily use), one will power up (not certain if from full off or standby) dimmer looking and with a tan overtone.  Powering it off and back on will always (almost always?) make it go back to normal.  I attached a couple pics.  The left one is the problem.  It usually looks the same as the right one.

Does anyone know what may be up with this?  Not sure if it is a big enough problem to worry about since it is flawless the rest of the time, but I've been reading about monitor problems and fixes here and it's got me curious...

Thanks,
Rick