Hi, We've been using 13168M in production for some time now (works great). I want to get us onto the latest build but am having problems getting NAT to work. Phones can register; can dial 9999 test #, but after 100 seconds the call is disconnected with error: 2009-10-16 19:52:26.936618 [NOTICE] sofia.c:4038 Hangup sofia/internal/1001@myhost.mydomain.com [CS_EXECUTE] [RECOVERY_ON_TIMER_EXPIRE] I took the standard internal.xml and vars.xml files from the new build and made the following modifications - which worked previously: modify conf/vars.xml and update <X-PRE-PROCESS cmd="set" data="domain=myhost.mydomain.com"/> <X-PRE-PROCESS cmd="set" data="bind_server_ip=1.2.3.4"/> <X-PRE-PROCESS cmd="set" data="external_rtp_ip=1.2.3.4"/> <X-PRE-PROCESS cmd="set" data="external_sip_ip=1.2.3.4"/> Modify conf/sip_profiles/internal.xml <param name="aggressive-nat-detection" value="true"/> <param name="ext-rtp-ip" value="$${external_rtp_ip}"/> <param name="ext-sip-ip" value="$${external_sip_ip}"/> <param name="NDLB-received-in-nat-reg-contact" value="true"/> <param name="NDLB-force-rport" value="true"/> <param name="NDLB-broken-auth-hash" value="true"/> The big difference I note is that on PRODUCTION (which works) "sofia status profile internal" yields: URL sip:mod_sofia@1.2.3.4:5060 BIND-URL sip:mod_sofia@1.2.3.4:5060;maddr=10.250.35.224 But on Test I see: URL sip:mod_sofia@10.250.66.210:5060 BIND-URL sip:mod_sofia@10.250.66.210:5060 Any ideas? Thanks, Chris.