Gotten from the voip.ms wiki, this YT vid from Abraham Moller

Click on FXS PORT1 and configure your settings accordingly:
Notice that it is necessary to use the same server for both the device and the DID number in order to get incoming calls correctly

Required settings

  • Primary SIP Server: servername.voip.ms (one of VoIP.ms multiple servers, you can choose the one closest to your location.)
  • Failover SIP Server: (Please leave this Blank)
  • Outbound Proxy: servername.voip.ms (Use the same server you used as Primary SIP Server.
    For firmware 1.0.15.4 and higher we recommend leaving blank the outbound proxy field
  • NAT Traversal: Keep-Alive
  • SIP User ID: (Replace with your Main SIP account or Subaccount UserID, e.g. 100000 or 100000_sub)
  • Authenticate ID: (Replace with your Main SIP account or Subaccount UserID, e.g. 100000 or 100000_sub)
  • Authenticate Password: ****** (Use the SIP account password - By default this is the same as the Customer Portal)
  • Name: Outbound callerID Name* See the requirements below.
  • DNS Mode: A Record
  • SIP Registration: Yes
  • Unregister On Reboot: No
  • Outgoing Call Without Registration: Yes
  • Register Expiration: 5
  • Allow Incoming SIP Messages from SIP Proxy Only: Yes
  • Preferred DTMF method: SIP INFO, RFC2833, In-audio
  • Use P-Access-Network-Info Header: No
  • Use P-Emergency-info Header: No
  • Enable Call Features: No
  • Dial Plan: {[x*]+}
  • Preferred Vocoder: PCMU, PCMA, G729
  • Enable Pulse Dialing: Yes
  • Pulse Dialing Standard: General Standard
  • Enable Hook Flash: No
  • Enable High Ring Power: Yes

Optional Settings

  • Gain RX: 0dB
  • Dial Tone: f1=600@-17,c=4/4;
    this gives it the old dial tone sound