Outbound calls "Forbidden"

I’ve got a FreePBX system setup, and I am having problems with outbound calls getting ‘forbidden’. He is the output from asterisk when an outbound call is placed:

== Using SIP RTP TOS bits 184 == Using SIP RTP CoS mark 5 -- Called SIP/Voicemeup-trunk/15062928928 [2012-11-25 14:24:19] WARNING[1539]: chan_sip.c:20274 handle_response_invite: Received response: "Forbidden" from '"Brian McCain" <sip:[email protected]>;tag=as41b709a8' == Everyone is busy/congested at this time (1:0/1/0) -- Executing [[email protected]:23] NoOp("SIP/1-00000042", "Dial failed for some reason with DIALSTATUS = CONGESTION and HANGUPCAUSE = 34") in new stack -- Executing [[email protected]:24] Goto("SIP/1-00000042", "s-CONGESTION,1") in new stack

Any thoughts?

You carrier doesn’t like the way you dialed your number, the CODEC you proposed or some other invite/SDP parameter.