Can't hear MIDI tracks in DP3-please help Options

Hi there,

I'm running a new G4 with a MOTU MIDI express XT and DP3 and I'm having problems. I can record the first two MIDI tracks that I record just fine but I can't get my synth(roland XV-88)to play back any track other than the first two. this is also the case if I try to record on track 3 by itself. I can see that DP3 is resonding to the keys I press because it's being shown on screen. also the midi express seems to acknowledge the activity OK. I have local control turned off and have reconfigured freemidi a couple different ways to no avail. any ideas on what to try? is it a setting in the synth itself? is it DP3?

thanks a bunch for your help