Switchvox - Why Does The Number Dialed Change on the Phone Display During A Call?

You most likely have a Gateway appliance in between your PBX and provider.

To resolve this issue please log into Gateway appliance.

1. Go to Configuration > SIP Endpoints and modify the SIP endpoint.

2. Turn on 'Enable Advanced Options' and go to Call Settings Tab.

3. Set 'Send Remote-Party-ID' to NO and then test.