Thanks for the responses. The system is running at the 7.29 codec. However we had been at 7.11 when this issue started, so changing the codecs havent helped. They have all IP phones, locally (where the Officeserv is) the call quality is fine.

You raise a interesting idea with the volume gain, but is'nt that setting system wide, it may make the volume too high for the local users.

We are using MPS and we opened the VPN per Samsung instructions, anything else I can try?