I have setup a IPSEC VPN from Epygi to Remote Sonicwall in order to get around NAT issues for a remote extension

The VPN is built ok and my extension registers but I just get one way audio

The remote site can call the Epygi site but cannot be heard by the recipient of the call

I have doen loads of tests and research. I have added remote subnet to NAT exclusion lists, disabled NAT Traversal etc

As part of my troubleshooting I am doing some ping tests

I can ping the epygi LAN IP from the remote site
I cannot ping the remote phone IP from the epygi

Shouldn't I be able to do this?

Any thoughts where the problem might lie

There is nopt firewalling on the VPN