Mikrotik – Fix srcnat issue (script)

On mikrotik router create a new schedule

Name: SIP-NAT-AUTOFIX

set interval to 00:01:00

on event:

:if ([/ip firewall connection find src-address=”ipofpabx:5060” and protocol=”udp” and srcnat=no]) do={ :global LastSipTimeout ([:pick [/system clock get date] 0 12] . “_”. [:pick [/system clock get time] 0 9]) }
/ip firewall connection remove [find src-address=”ipofpabx:5060” and protocol=”udp” and srcnat=no]

Save and apply

Ensure you change phone system IP.