I just have the P2500, so I don't have pads--and never played a CS. Just wondering if there are parameters in OS 2.0 that related to the pads--sensitivity, curve, etc. or if they show up as a source in cords.
Hmmm:
"The velocity and pressure-sensitive keypads can play on any MIDI channel as programmed in the Controllers menu. They are normally set to play on the “Basic” channel, which means that they play the preset currently showing in the preset view screen. The keypads output channel (mono) pressure internally (routed in the PatchCords) and both channel and polyphonic pressure over MIDI."
Maybe that helps explain what's going on. Possible workaround: route pads out and back in. Can some DC be added to the destination for something so whatever is being affected doesn't drop so much.
Without a CS, this is all "in theory," but maybe it will help. It would seem to explain why you get the difference internally and externally (channel pressure v. note-by-note polyphonic pressure).
Steve
PS: I picked up a CS 4 x 4 knob PCB and was hoping I could turn it into a stand-alone midi controller--so I too, would benefit from that section of the service manual, too.