Assign tracks

I cannot seem to assign audio channels in Logic. I can assign chaamel,pair 1/2 into Logic track one. But wen I try to assign 2/3, 3/4 etc. No audio getting to Logic. I should be able to split out audio channels from Yamaha Motif into separate tracks in Logic. This has been extraordinarily frostrating, and I am wondering if you have any experience with audio track assignment?