Sounds like the typical chip problem. Run the following test: Power up the Juno while you hold the "Transpose" button down. The press bothe "Poly1" and "Poly2" at the same time so both lights are up. Press "Bank 2" and then press any note six times. The active voice is displayed in the readout. You'll see which voice is dead.
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Re: [vintagesynthrepair] Roland Juno 106S - note stealing ??
2013-05-23 by Malte Rogacki