Matrix12

[riccardo]

Hi everyone,
got this M12 which is patchwork of Expanders and a M12 shell and keyboard.
Each board works when mounted on the original M12 that I have.
Only voice boards do not tune. But Cem chips are all right when socketed
into the original M12 voice boards.
Error message is Voice 1 processor malfunction.
Also sometimes is Voice 0 processor malfunction.
Subtitution of main processor of the boards has no effects on the error
message.
Anybody can give me a clue?
Ciao, riccardo