Antix

Testing the switches with a multimeter I am seeing how they do not make contact anymore ... they have become like resistors...after 25 years :)

Sounds like fun :) I´ve got a 10 years old Roland Vsynth here, which i really love, but a few interface tactile switches are also beginning to fail - as well as the LCD backlight sometimes stays off (CCFL based?)... Hope there is replacement parts to be found somewhere :) - anyways, the D50 is an awesome synth, never part with it ! :)

old gears may give these craps.

My S1100 LCD is very dark .I read that it is a common defect on old Akai and on Ebay I found a backlight replacement.

I hope it will works.

I think you can find something like in the net.