Press J to jump to the feed. Press question mark to learn the rest of the keyboard shortcuts

3rd party SIP Phone cant call remote offices

I have a Konftel 300wx with IP Dect 10 base and have the phone configured to register to CUCM 7.1.5. I am able to make and receive external calls (PSTN) and can also call internal numbers within the same office.

My issue is when this phone tries to call another office (WAN) the phone rings on the far end but as soon as they pick up the call ends.

Any ideas?

100% Upvoted
This thread is archived
New comments cannot be posted and votes cannot be cast
level 1
Original Poster2 points · 2 years ago

It's a codec issue. It looks like the Konftel is not using G.729 which is what our CUCM is expecting. I tested a small site by changing it to G.711 and then it worked which proves the theory. So my effort now will be to see how I enable G.729 on the Konftel. More to come...

level 1
Original Poster2 points · 2 years ago

So issue is resolved. I just had to go into the Dect 10 web interface and reset the codecs and then all of a sudden G729 appeared on the list. I guess its not enabled by default. Once enabled and move it to the top of the list and the calls are now working.

level 1

ACLs or NAT?

level 1

Is it only the Konftel that is affected? What about other IP phones? Are they SIP or SCCP? Also, what happens if the Konftel receives a call from another office?

Offhand, it sounds like UDP is being blocked at the WAN interface.

level 1

It is a codec issue. You could enable MTP required on the device to address the issue as well, considering you have proper media resources configured.

level 2
Original Poster1 point · 2 years ago

I tried that but it didnt work for me.

Community Details





Create Post
r/Cisco Rules
No Brain Dumps
No direct sales of equipment
Cookies help us deliver our Services. By using our Services or clicking I agree, you agree to our use of cookies. Learn More.