Volumio does not show up in Airplay device list

Hi all,

I have Volumio v 2.185 installed on a Raspberry 3.
When searching for Airplay devices on my Mac or iPhone, Volumio cannot be found.
However, it can be found with iTunes as upnp device, as well as with Spotify on my iPhone (but not with Spotify on my Mac).

Do you have any ideas what the issue could be or which modules have to be checked?

btw: there’s also an instance of Fhem running on this volumio distribution.

Thanks and best regards!