One way audio on incoming calls. on hold the off hold and have audio


(Dan S) #1

I have he dreaded issue with one way audio till he callis put on hold then off hold. This is for a new set of SBC’s with level 3.

I have a Private connection from level 3. So no Nat.

level3 8.49.49.141 to my ip 10.123.244.169 thats my isp. firewall is off. Ports to L3 open in security group for all nat to here range.

10.123.244.169 to my 10.123.245.18 host. Ports for udp are open in Security groups. No denys in firewalls are found.

my host 10.123.245.18 to my zoiper client.

Call comes, I see the data. I see when I put the call on hold in wireshark I see it does a new invite but the ports stay the same for rtp and now audio. Not sure what I have wrong.

In he rtp data it says I loose a bunch of packets but its the direction I have audio in. so that the only clue I have so far.


(H.Yavari) #2

Please check the first invite SDP for rtp ip.
this issue is related to NAT.
Is it enabled in sip settings? did u configure Extern ip and local ip??


(Dave Burgess) #3

It is also a symptom of the outside network access device (firewall/router) not forwarding UDP ports 10000-20000 to the PBX.


(Dan S) #4

so im in office for testing and I can’t get it to fail, nor can I get it to fail on vpn users. Level 3 uses port 5000 to 65000 for rdp on there hosts. and they also separate the sip registrations to a different host then the rtp or media is from.

I hate failures that aren’t constant. Somewhere there is a chaos in a place I need to have order.