No, I think what you've done is a bad idea. There is a reason why your joystick is misbehaving and you need to find what it is rather than patch in additional components.
If you go to the files section for Poly-800 servicing you will see the schematics and also a great explanation of how the joystick electoronics works.
/Mike
On Saturday, October 18, 2014 5:26 AM, "ultragalore@... [korgpolyex]" <korgpolyex@yahoogroups.com> wrote:
I have a problem with the Poly after my HAWK800 / atomahawk kit. The joystick DCO seemed to be miscalibrated. I need to pull it half an inch down to have proper center value.
For those who are fiddling with this also, I managed to calibrate the Y-axis by putting a 50K variable resistor between pin 16 an 5 on the IC6 analog multiplexer IC: