My keyboard won't power up at all. It hasn't been used in over a year. It is a Yamaha Clavinova.
It says CVP.30 I don't know what year it is as we got it second hand but its at least 7 years old. It did work fine until last year.
I don't understand what you mean by power supply? Do you mean the plug? It did work fine for the first couple of years.
No it doesn't have a black box. Its a normal plug and we have checked the fuse already
No, that doesn't make any difference.