Hello,
What do you trig from the sequencer ? midi note on ?
The numbers shows up when the preenfm2 receive midi note on... So if you send CC for example, you won't hear anything and won't see anything.
Have you checked sending the same sequence to another sound module ?
Or even better to a midi monitor program on your computer ? That would allow you to understand exactly what the octatrack sends.
Let me know what you find,
Xavier