[TenTec] Orion screen

[G.C.]

Dear friends,

I have just noted on my TT Orion the LCD screen become darker on the upper left screen side about one hour after the power on.
It seems more evident if the external temperature rise, here we have now about 30°C - 33°C
Any idea about this fact? Any possible correction? Could be the LCD screen defective?
Should I contact the TT service?

Thank for your help.

Beppe IZ2ABU