We are having an issue with call forwarding our calls to an external number using our CME. Inbound and outbound calls both work with out issue but when we call forward our calls to an external number (like a cell phone) and someone from outside calls in the caller doesn't hear ring back and when the called user picks up their cell phone there is no audio in either direction. Here is the call flow.
PSTN --> SIP --> CME --> SIP --> PSTN
