Hmm, still think your issue must be around Avahi setup. I had Avahi running at the start too, it just wasn’t – by default – configured correctly.
I’ve used Ethereal/Wireshark to look at what happens on my network when a) Firefly starts, b) when iTunes starts on a second PC and c) when iTunes on the second PC opens the Firely Server.
In cases a) and b) there’s a flurry of multicast packets going out from each host where the service is starting – Ethereal shows them as MDNS (multicast DNS, obvsly) but no IGMP.
All my traffic is local to a single IP subnet so the router’s not involved other than bridging the wireless segment to the wired.
(Just noticed that my most recent Apple Airport Express – the new 802.11n version – is chatting IPv6 as well as IPv4, shall bear that in mind for any funnies)
I’ve used avahi-discovery on my Ubuntu instance to see what’s out there, here’s a snapshot of what it sees (colossus is the Ubuntu instance, helios a Nokia N800, the two Windows PCs don’t show as wkstns but one of them is hosting ‘Firefly Media Server’ while ‘Firefly svn-1696 on colussus’ is self explanatory).
