Discussion about the Korg PolySix synthesizer

Update:

I've checked with my second clone board - same behaviour for PW zero.
Fortunately I still have one somewhat battered original board - there is a
bit fuzz on the PW signal but not this very clear sine signal as with my
two clone boards. So either it's something I did wrong when assembling the
clone boards - or possibly another clone board error.
I've also tried both old and new boards in a number of different Polysix
chassis with different voice boards - all showed some kind of "fluttering"
to some degree. The "fluttering" is not related to the LFO or PWM speed.