Hi david64, Thank you for your reply, The answers to your questions:   What is the model of your wifi router? TP-Link Archer VR1600   Is the Yealink an analog or IP phone? IP phone   An IP phone connects to router and is programmed with the VOIP provider's details. Same deal with PC/Softphone. Already configured with the Nexttelecom connection details. As i said was working fine when FTTN was the connection.   If you have a Bundled NBN/VOIP plan, there was a router config change going from FTTN to FTTP to disable VLAN tagging. This can't be an issue else the internet would not work. No Bundle, phone is connecting out my work phone provider not a TPG account.   Did you do factory reset on the router at changeover? There might be some missed setting. No, I was told there was nothing to change in the modem. Internet is working fine.     Can you find out from Nexttelecom the target ip addresses and port numbers for the phone functions. On your PC, use telnet command to check the end to end routing. No target IP address, It is a web address in both cases that the phone and softphone connect to. Which i can connect to when using a web browser no issue.     ... View more