True wind speed not showing on I70

Hi,
...just posted the question re shared Charts, but there is a second issue with my system.

Whilst the appearant wind speed is shown on the I70, I don't get any results for the "true wind" Speed.

We are moored in a marina and I haven't tried when sailing, but I don't see any reason why it doesn't show.

I am not sure whether this is important but we have no speed/depth transducer built in yet (but GPS and EV1 should tell the System that we are not moving).

My System (Axiom MFDs, Evolution 400, 3 I 70, 2 control heads for the Autopilot), wind transducer via ITC5, Quantum Radar).

Does someone have a clue as to what I could do?

Thanks,
Joachim