Strange green blink during boot up

[arncalars]

I´m very happy with my iMac 27 late 2013.
The last few days it shortly blink green during boot up.
Everything works fine, but just before the Apple-logo and user accounts appear, the whole screen turns light green for a short moment.
I have disconnected everything and run diagnose test (D key during boot up) and no problems found.

But why the green issue. Does anyone know ?

Regards Lars

 

[maflynn]

There was a thread a little while ago where the screen blinked for the member and resetting the pram fixed it

Give that a shot to see if it helps.

 

[arncalars]

There was a thread a little while ago where the screen blinked for the member and resetting the pram fixed it

Give that a shot to see if it helps.

Perfect - worked - Thank you.