We have deployed the ST switch as recommended For the ISDN to SIP Migration , and inbound calls have been tested successfully. We are now experiencing an issue with outbound calls. Every outbound attempt fails immediately with a "Request Denied" message.
I’m currently experiencing an issue with our SIP trunk using the SG 220E1. I have already configured the trunk, trunk group, and SIP profile. However, when I perform a test call, I experience one-way audio. The caller can hear the recipient, but the recipient cannot hear the caller.
I have also verified that the required traffic is already allowed through the firewall. I would appreciate your assistance in troubleshooting this issue and identifying the possible cause of the one-way audio.