I noticed exactly the same problem when I bought Stella. I’m pretty sure that my system was configured as original from Amel. (Previous owner did not change anything).
I cannot find out right now exactly what source setting I used in the Hydra, but I’m fairly sure it’s not 16.
BUT the important thing is that you need to make sure that the Navnet3D system is actually connected to, AND is sending out heading data to the Hydra.
This is configured in the setup/installation process, and on my boat this was not turned on by Amel/Pochon.
So, in short the process is:
1. Find out which NMEA data Out port on the master MFD is physically connected to the Hydra.
2. Make sure the MFD is configured to send heading data on that port.
3. Set up the Hydra to use that data.
I’m sorry I cannot tell you which port numbers to use because I’m travelling at the moment. Regardless, your boat may not be wired exactly as mine, so you should go through the process yourself.
Hop that helps a bit.
Sent from my iPhone X