Hello everybody, I just subscribed here though i've already setup three Elastix boxes.I used the 2.0 version for the first time and i need your help. Let' start from the hardware. P4 CPU (S478) @ 2.4GHz. ASRock mobo with 512 DDR. HFC-S ISDN BRI card. The only problem i have got is that there's no audio between the remote extensions though they register normally.Dyndns account has been used on the Speedtouch 536i and it updates normally. The following ports have been forwarded to the Elastix internal IP: 4569 UDP IAX 5004 - 5082 UDP and TCP SIP 10000 – 20000 (UDP) RTP 443 for Web access. All Port Forwarding entries were carried out with CLI commands using the following syntax: nat tmpladd group=wan outside_addr=0.0.0.1 inside_addr=192.168.1.64 protocol=udp outside_port=4569-4569 inside_port=4569-4569 The SIP ALG has also been disabled using the followin commands: :connection unbind application=SIP port=5060 :connection bind application=SIP port=5061 I have to mention that everything worked fine with Elastix 1.6.I switched to 2.0 because the old version did not recognise the ISDN card. At sip_general_custom.conf the following lines have been added: nat=yes externhost=my_domain.dynalias.org localnet=192.168.1.110/255.255.255.0 externrefresh=120 qualify=yes I also added these lines to the sip_nat.conf file but there was no result. The rtp.conf file also has the following enteries: rtpstart=10000 rtpend=20000 Initially i thought that there was something wrong with NAT.So i performed Reset To Factory Defaults three times and re-setup the router configuration.I also installed a second Speedtouch 536i just in case there was something wrong with the first one.Now i've run out of ideas and i need your help badly. Eagerly waiting for your guidance. Thanks in advance. George.