Hey,
I just bought a used KT 88, which works fine, except that when I plugged in a Yamaha sustain pedal, the sustain effect is reversed. No pedal- sustain, pedal down - no sustain.

I was told to "reverse the polarity" within the system properties, but the only setting I could find only talked about having sustain on or another effect on.

I'm not too experienced with the inner workings of midi or keyboards, although not a complete newbie, and any help would be greatly appreciated.

Thanks,
Dave Wood

Try unscrewing the pedal (on the bottom usually) and removing the cover. There should be two wires connected to two poles and resolving your problem should be a simple matter of switching the wires around.