Our German client is fowarding phone calls from their own b2b clients, based mostly in Germany, to our company also based in Germany. For the last few months we no longer ‘see’ the original caller id of the client’s client, only the caller id of our client.
We are running Asterisk 1.4.22. We have confirmed with our Telco provider that the client really is forwarding the original caller id. So the problem must lie with the way Asterisk is handling the caller id? We have made no significant changes to the Asterisk server in recent months that would explain the change in behaviour. The client has recently changed their number format to E.164. We have checked the normal Asterisk settings which control the caller id display.