FreePBX version 15.0.37.4. Trying to connect a remote VOIP phone to PBX using CHAN_SIP configured extension going over IPSEC VPN tunnel between two Synology RT6600AX routers with point-to-point tunnels between them. Phone registers and can make and receive calls OK. But no voice can be heard in either direction, just dead space when talking or listening. Are there any configurations I am missing on the extension or other modules of FreePBX that would allow for the voice to be heard?
Thank you for your assistance on this.