OB plugin not receiving midi

Hi, I have OB as a plugin on a track in my DAW (Harrison Mixbus 32cV6) connected to my Digitone. All is fine, DN is recognised and I can play it from the virtual keyboard.
I have an external midi keyboard, it’s recognised and routed to the OB plugin, I can see the midi coming in on the track, but no sound from the DN. Is it at all possible to use an external keyboard to play the DN using OB?

Thanks!