Tried the contact cleaner & cotton buds, it made no difference. Hooking the unit upto a MIDI interface, the dead keys show no output to the PC, but I am able to generate sunds via the Midi software (Anvil). I think there may be something more than just dirty contacts. hence the request for any schem...

G'day, Just joined today, and after browsing for awhile looks like some good stuff around. I have just picked up a Ensoniq SQ2 cheap ( dead keys)., and I am after a schematic as a priority, and then a users manual, any hints at all. I have a good knowledge of Electronics so I am not afraid of gettin...