SIP/SDP headers contain inconsistent information

[AbdulKader Anwar]

Hi there,

We got an issue with extensions getting incoming all from another extension which is supposed to go operator. When i check the Activity Log and found the below.

02/20/2019 12:49:37 PM - NAT/ALG check:L:61538.1[Extn:4151] REQUEST 'INVITE' - some of SIP/SDP headers may contain inconsistent information or modified by intermediate hop Media session IP ('c=' attribute) is not equal to the IP specified in contact header: Media session IP:0.0.0.0 Contact IP:10.2.7.40 Media session IP ('c=' attribute) is not equal to the SIP packet source(IPort): Media session IP: 0.0.0.0 Received from: 10.2.7.40

is it normal or any issues there. Can someone have an eye on it and help me overcome the issue. It is not regular but happening randomly.

K'nd regards,
Anwar

 

[YiannisH_3CX]

Hello @AbdulKader Anwar

We will need more information about the PBX setup like where is the PBX installed? Is it local or remote? Also are the phones local to the PBX or remote?
Have you run the firewall checker of the PBX? Does it pass all tests successfully?