> Thought so.
>
> I wonder if there is any way to modify this. I guess it's not that much effort to just tune them :D

If you are familiar with electronics that's possible. You have to take the control voltage from the tuning potentiometer of unit #1
and add it via a suitable summing resistor to the common pitch node of unit #2. But this requires some soldering and wiring between
the 2 units.

Best wishes
Dieter Doepfer