The friend of mine had the same problem- stripes on display and bad seen .
So he disconnected display and connected a navigator to video out on Yamaha s back, and no problems.This occured at home and was no hurry.
Another friend had a broken display just before the gig when turning on a keyboard. He called me for help as it was 150 km from nearest town. I advised him to find a driver who owns a navigator with video input. He called me back in 30.min. --NOBODY HAS !!!!
Then I gave him another advise , as it was a small hotel - to find a TV set with video input and a cable with RCL ends.
He was lucky, connected to a 32" Tv and played the gig, what a strange feeling ,he said, to wiew such a big monitor at the wall .
And I am still waiting for WHiskey bottle -for advise !!HA HA!!!!!
this should be a common problem for thi model- two of my friends got it and few more.