Pro one - no sound

I have juste received the pro 1 but I still can't get any sound out of it.

I already own a neutron so both are side by side and their midi settings are the same (channel 16)

I use an arturia keystep as master keyboard.

neutron is working nicely but when I'm plugging the audio out of the pro 1 instead of the neutron I don't get anything. I don't even know if the the pro 1 is getting my midi as there is no led for that purpose like on the neutron.

Is there something I missed ?

Also it seems there is no updater tool for the pro one on the support downloading page.

Thank you for any hint.