Depending on the version of SonicOS your screen may appear slightly different. Log into the web interface on the SonicWall.SonicWall has a feature called SIP Transformations that consistently cause total or partial loss of voice. This KB applies to all SonicWALL SonicOS firewalls. In browser browse to 192.168.0.1 (this is the default IP address)The default username is admin and the default password is password.This guide applies to most Netgear routers From the CLI: To verify if SIP ALG is enabled or disabled run show security ALG status | match sip.Type: telnet 192.168.1.1 (Enter) NB – Ensure Telnet is enabled ( Start | Control Panel | Programs | Programs and Features | Turn Windows Features on or off | TELNET CLIENT > OK).This guide specifically applies to the Vigor 2760 but is also applicable to most other DrayTeks in the series.
For TCP run: No ip nat service sip tcp port 5060.