When trying to connect from a sip-phone to the portal, sip.allstarlink.org using,

sip://1:allstar@sip.allstarlink.org:5060/0
-or-
sip://1:allstar@sip.allstarlink.org:5060/<node_number>
-or-
sip://0@sip.allstarlink.org

It connects, but there's no audio. No errors.  PCMU@8000 correctly negotiated.  I've tried two SIP-phone clients and a FreeSWITCH user-agent with the same negative outcomes.  I've tried variations on the connect stream with same negative results.  The BRIA soft-phone even handshakes GSM but still no audio.

Is there something I'm missing?

Thanks,