Yamaha CS80

Hi everybody,

I have recently purchased JH's CS-80. However this machine requires
some fixing. While I have access to a qualified service engineer, I
would appreciate some feedback, hints, tips from you guys before I
give it to him.

1)Suboscillator does not work: no matter what waveform selected, there
is no modulation on either VCO, VCF or VCA. Speed does not do
anything. As a consequence the corresponding aftertouch features do
not work either.  Routing Noise to the parameters mentioned above does
result in (some) effect. Any ideas?

2)One of the keys always at max: it seems that one of the keys always
produces maximum velocity, no matter how it is hit.

3)Only the top two thirds of the ribbon controller work (somehow):
when I touch the velvet, it almost feels as if the bottom third were
not existing. Can ribbon controllers be fixed at all (or replaced?)

4)Kenton Midi Kit: have the kit and want to have it installed, any
tips from your side?

Thank you so much for some feedback
Peter