Old AudioCodes devices suffer from a problem where they replace 127.0.0.1 address in Record-Route headers (added by Sipwise C5’s internal components) with the device’s IP address. Supposedly, the whole range of AudioCodes devices with a firmware version below 6.8.X are affected. As a workaround, you may enable the topos feature to stop sending Record-Route headers out. To achieve this, execute the following commands:

ngcpcfg set /etc/ngcp-config/config.yml kamailio.lb.security.topos.enable=yes
ngcpcfg apply 'enable topos for audiocodes devs workaround'