I have a nec 9000 pj with 1800hrs red & blue guns perfect, green gun will not behave .Problem only started 2 days ago , have owned pj for 14 mths no faults .Green has poor focus across all of raster area.have checked astig,optical & electronic focus. EM focus coil adjustment will not fix it either. focus quality improves but gets nowhere near quality of other guns when either red or blue gun is switched off with remote.Green lines are approximatly twice as thick as red with haze worse on horisontal lines .When cables from video board to gun is swapped red to green ,the fault transfers to red gun and green gun clears.when video input cable to video board is swapped red to green ,fault stays on green gun .I suspect the video board (video out pwb) is the culprit but need help to diagnose further ,I do not have access to another video board to try.Any assistance would be greatly appreciated thank you .............blakey.