Hi Jerry,
The Yamaha volume pedal standard is completely opposite of most of the rest of the world:
Ernie Ball/Roland/Old Korg Standard --
Tip = potentiometer (pot) wiper
Ring = voltage reference
Sleeve = ground
Yamaha/New Korg Standard --
Tip = voltage reference
Ring = pot wiper
Sleeve = ground
In case you're not familiar with the names, a standard 1/4" guitar cable has only the "tip" and "sleeve" connections; a stereo cable adds the "ring" connection between the tip and sleeve.
This could be part of your problem. If you need to use a Roland pedal with a Yamaha synth, or vice versa, you have to swap the "tip" and "ring" connections on the stereo 1/4" plug, or the pedal response may be quite erratic. This can be done by cutting the plug off and soldering on a new one, or by making a short adapter cable (1/4" stereo jack to 1/4" stereo plug) that crosses the wiring inside the adapter.
Regards,
-BW
--
Bruce Wahler
Ashby Solutions™
http://music.ashbysolutions.com978.386.7389 voice/fax
bruce@...