The Yamaha AN1x Synthesizer mailing list

> I recently installed the AN board in my CS6X but it has a strange
> bahaviour... Each 5th note I play sounds different from the other four, and

That "Each 5th note" Problem Sounds familiar to Me, But Not in my AN1x, but in 
A Juno 106: Corrosion Caused by time on the controller. But in case of a VA 
Synth, that is impossible! Could be very impressive if the engineers could 
even emulate those factors on the synth! ;)

Have you tried replacing it on the store?