a3k/nord triggering from rm1x: help

[cris f]

Hi, i'm using my a3k for a piano line in one of my tunes, but for some
reason, notes that are being played by my nord are also be played on my a3k.
Has anyone experienced this type of problem where the midi notes from one
machine are being triggered on another machine?  Any tips? It wasn't
happening in my soft seqencer, so i'm wondering it the rm1x is the culprit.
Thanx in advance,
cris f