If you are receiving calls going silent or receiving MEDIA_TIMEOUT issue, check the following:
1. Are all the media ports/regions required for the trunk used (twilio/chime) have been allowed in the firewall?
2. Are the issues reported newly? How many agent/calls are affected by this?
3. Share the screenshot of all the firewall ports configured/allowed for the dialer.
4. If agent calls are being received with MEDIA_TIMEOUT , are the agents able to hear the beep tone played?
5. Is it a new setup ? Was the setup working earlier? Was there any network changes done due to which these issues are seen?