Multicast / Paging / Intercom - Yealink T58

[jolouis]

When you initiate the page does the phone at least look like it's doing something, or does it just fail/sit idle?

If the screen changes to look like it's on a call, try running a Wireshark trace or some other kind of packet capture on the network and see if there are any multicast packets streaming over the network (ones with the address that you specified as the destination). That will at least tell you if the sending side is working.

Once you know if that is working or not you can then focus on the receiving phones and further troubleshoot from there...