Troubleshooting RINGING

If user complains that he does not hear ringing on his device when call is in progress:

1. Configure your phone with same settings as your users and dial same number

2. Enable sip debug and full log and look for similar message:

<--- Transmitting (NAT) to 78.86.167.126:49180 --->
SIP/2.0 183 Session Progress
Via: SIP/2.0/UDP 192.168.1.67:5062;branch=z9hG4bK-14a55d2;received=78.86.167.126
From: "88810006" <sip:88810006@67.215.68.110>;tag=9b2a4f73db3575ao2
To: <sip:12462303496@67.215.68.110>;tag=as226a5ec3
Call-ID: e75ba6fb-b9fc9d26@192.168.1.67
CSeq: 102 INVITE
User-Agent: MOR Softswitch
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY
Supported: replaces
Contact: <sip:12462303496@67.215.68.110>
Content-Type: application/sdp
Content-Length: 253