S10 discovery across vlans

I have my new S10 installed and working .
What doesnt work is ‘discovery’ of the device across vlans.
Currently my openwrt firewall setup allows discovery of a Denon AVR and a chromecast gen II across my 2 vlans .
So far I’ve been unable to determine whats different about the S10 .

SSDP ?
MDNS ?

something else ?

@pluffmud the arylic device and the phone running the 4stream application must be on the same vlan.