Disable source port rewriting

By default AZTCO-FW software rewrites the source port on all outbound traffic. This is necessary for proper NAT in some circumstances such as having multiple SIP phones behind a single public IP registering to a single external PBX. With a minority of providers, rewriting the source port of RTP can cause one way audio. In that case, setup manual outbound NAT and Static Port on all UDP traffic potentially with the exclusion of UDP 5060.

In old versions (AZTCO-FW 1.2.x and before) the firewall performed static port NAT on UDP 5060 traffic by default, but that is not desirable now because it breaks more scenarios than not currently. However, in cases where static port on UDP 5060 is required, configuring manual outbound NAT to perform static port NAT for udp/5060 will allow it to function.