You are working in a service provider voice NOC supporting a national VoIP network. The network underwent a capacity expansion that added voice bearer trunks to a newly deployed media gateway. After…

You are working in a service provider voice NOC supporting a national VoIP network. The network underwent a capacity expansion that added voice bearer trunks to a newly deployed media gateway. After the new trunks were configured and placed into live service, the service desk began to receive complaints from end customers that their VoIP service is not working for certain calls. The service desk is unable to resolve the problem and due to increasing troubles coming in, they escalate to you. Assuming that all physical layer option settings are verified to match carrier-provided specifications, which action should you take to isolate the problem before escalating to the PSTN PTT carrier?