We are running Asterisk 11.19 in an Amazon EC2 instance and it works well for us overall. We use ConfBridge for internal meetings. My dialplan does not provide any access to the conference rooms from an outside line. My EC2 instance is behind a firewall with holes open for the fewer than ten total SIP phones that use the PBX at all.
During conference calls, we occasionally have a completely unrelated phone call barge into our room. It usually sounds like we originated a call, that is, some automated attendant suddenly starts listing their company hours and menu options. Occasionally a human answers. Once, when we got a human, we had a brief conversation with her, indicating that the audio is live both ways.
The interruption is pretty consistently short, perhaps 20 seconds and not more than 30 seconds.
Naturally, all the standard call progress logs show that nothing happened. Our asterisk did not log any call activity other than the participants dialing in to our confbridge in the first place.
Is there anything I can do short of logging every single RTP packet to figure out what is really happening here?