Midi And Mac, cannot receive midi signal in Reason 2.0 Options

[wingman]

i am running G5 DP 1.8 with Tascam US-122 midi/audio interface, and E-MU PK-6 midi keyboard. Have followed all basics: set midi preferences within the program, selected track for midi, and even secured all cable connections, but still cannot receive Midi through Reason. Tascam acknowledges signal in from keys, but no sound is produced. What is going on here, and is there anything I can do about it?