Kid Yoshi and I have been discussing this over email as it appeared to me to be a problem with his specific unit initially. Just a little update in case anyone else is running into this issue. My latest comments to Kid Yoshi on email:
I have replicated your issue on both the unit you returned to me and another unit in my studio. So, it’s definitely not related to the specific units you’ve had in your possession. I’ve also come to understand why my testing was previously inadequate–I believe I tested this parameter with fairly fast LFOs looking for a vibrato-type effect which is quite achievable. This does not properly test whether the parameter covers the +/- 6 semitone range claimed in the manual. All that being said, observations so far do not resolve the question of whether it a hardware or software issue at its root. However, I do suspect (and hope!) it’s the software. I’m reviewing how I apply this parameter in the synthesis and realized that I cannot explain how it would achieve +/- 6 semitones effect. So, I’ll study it further and hopefully identify a firmware solution.