Elektron Musical Instruments

I'm sure this is a very basic question, but this is the first time 
I've tried to use my MD with external gear.  I just want to sync my 
keyboards arpeggiator with the MD, I have set the keyboard to receive 
the external input, it reads the tempo but when a pattern is played 
it (the keyboard) plays notes triggered from the machinedrum.  If the 
kick drum plays, the bottom note of the keys play and so on.  
Basically the MD keys are acting like a Midi keyboard.  I haven't 
found anything in either manual that exactly solves my problem.  I 
just want to play my keyboards along with the MD pattern, synced up 
without the pattern triggering unwanted notes.  Thanks in advance for 
any suggestions, -Scott 

p.s. I'm using a Novation K-station keyboard