I once had to bring in one of my my Psr9000 arrangers.. to a so called Authorized Yamaha Service person in a big Local Music store not too far from here to replace a worn broken keystrip Arggggg.....which if anyone knows who had this happen will when a certain Key is depressed will emit the Loudest sound at maximum loudness versus all the others because the key contact has torn thru the strip. Anyway....after 3 days of waiting thank goodness I was off....I picked it up from the store after a call saying it was ready......after getting it home and trying it before a big gig that night I notice that the key is repaired
and works as it should, BUT.....I now have NO Display!!! needless to say some how this idiot so called Authorized Service tech screwed up and didn't reconnect they Display Plug inside after the repair......
I could barley see the LCD lettering through the screen if I used a FLASHLIGHT as a reflective device.....and without exaggeration had to go to the gig and perform for 4 hrs like a blind man using the maglight flashlight to make all my changes & played the whole gig that way......the next day I went back to the store like a raving wild man to blast the crap out of this jerk.....he says "Just leave it and he'll get to it sometime this week " due to all the other work in front of mine....so I marched into the offices of the owners which I personally know and talk them the story of what happened......& that I had a full gig schedule that was being hindered by this nincompoop.......they were so angry....the owners went to the back of the store repair room and blasted this guy making him open the keyboard and see that he INDEED left the display plug terminal off causing the problem.....its was repaired......he was reprimanded....they apologized....I was happy.....& off I went into the sunset to make more music....

Dont always trust these so called AUTHORIZED service centers......its all about money not about your satisfaction most of the time....Buyer Beware!