Missing pixels on radio Display?

[Justintime]

I noticed this recently, my 06 320D SE seems to lose pixels on the radio display when its hot out. Dosen't happen in winter with the heater but definetly the last few days its gone screwy. Seems to be ok when cooler (say below 20 or so) Should i worry about this? Seems this car has every known 3 series problem available

 

[Justintime]

Its the 'business radio' whatever that is. The pixels do come back when cooler. Only when the cabin is excessively hot it happens.

 

[Justintime]

Checked last night and this morning, all pixels are back. Guess i'll leave the window down a crack to let some heat out.