I have tried switching the cables. also, it's not an issue when I use headphones. what makes me believe it is the synth and not the speakers, though, is that it's only an issue with layer A. any other sound sources through the speakers are fine. also, I'm using a centerpoint speaker, which is a stereo speaker in one cabinet. I'm thinking now that maybe the panning feature on the P12 isn't compatible with the centerpoint's stereo imaging technology.