Info screen on my RX 450h series 3

[VFR]

When my headlights are on either by selecting auto or manual “on” the screen brightness will often suddenly dim to about half what it is normally (enough that it catches your eye)

This is the info screen in the center of the dash (and in my case) tells me the state of charge etc as I always leave it on that view as it suits me.

Also

The blue downlight / background light that shows either side of the speedo dials etc will often go off & on but this has been going on for at least a year (or 2)

Serviced today at Lexus Exeter as my car has now reached 10 years, so I wanted to raise this issue as looking at what is covered by Lexus warranty it seems that the infotainment screen etc / dash screen etc is covered ?

They reported back that the tech found nothing  wrong and yes with the headlights on it will dim as is normal, but it has never done that before (i said) and should that be the case why does it go dim & light as I go along ?  Could it be the sensor that I guess it has to determine the level of daylight etc at fault (?), if is causes you any problem Sir then please come back (in my case just over an hour away)

So as I said I have not noticed it before (this dimming) but am I missing something as yours does it all the time ?

The blue backlight behind the speedo is definitely a fault but I know that they bulk at pulling something like that out to charge an LED.

Thoughts ……. ?