No audio in on my Sub 37

First of all a confession, I am a total ignoramous so keep any reply simple, really simple. I have just bought a Maschine Mk3 so that I can create some simple audio to send to the Sub 37. I know there is audio on the line out of the Maschine because I can plug it into the amp and hear it. However, when I plug it into the audio in on the Sub 37 and press a key on the Sub 37 all I get is the key I’m pressing, nothing is coming through from the Maschine. What am I doing wrong?

Make sure that the FDBK/Ext In light is on and that its level is up

You have to make sound with the Sub37 too.
Otherwise the signal won’t get through.
(so play a note and latch it for example)

Also note you have to set the fdbk/ext in to ON in the mixer sectionand that level up. (lowest POT in the MIXER section of the S37)

Thank you so much both of you, this was so helpful.
Nic

No problem.