[VoIP] How to workaround SIP-ALG when the main router does not have the option for disable it

This short video describes how to workaround SIP-ALG when the ISP modem does not have the option for be disabled. The SIP-ALG on most routers, only targets devices with port 5060 on the local network. With this small procedure, the issues derived from it, will be gone after being applied.
Also on the PBX server should be changed.

[@paradigm_nice4743]

Hello, we have a Grandstream GXV 3380, and we need to disable the ALG protocol on the router, but SFR is saying it is not possible to do so. Could you please help us?

[@user-yk9sk7pg6v]

Hello, I do not have personal access to the internet router/modem - will I be able to disable SIP ALG? Clients cannot hear me on one app (one-way audio), and on another app, calls are oftentimes dropping. I was told to disable SIP ALG in order to resolve the issue.

[@_disruptive_telecom]

You have the option of changing Local SIP port on each SIP device. Or raise a VPS with VPN configured, then connect a modem (or RPI) through that VPS, and also connect the phones to route the traffic via VPN. The issue is gone also using this method