Dear Mykola,
PBX (like asterisk) not support amr, try using TCHF/TCHH (not AMR).
see this :
https://community.asterisk.org/t/support-for-amr-codec/73659
hope this help!
On Fri, Dec 14, 2018 at 4:51 PM Mykola Shchetinin <mykola(a)kingmuffin.com>
wrote:
Dear Osmocom community,
Did somebody try to use nano3g ip.access femtocells and Osmocom system with
external call handling? What I am trying to do is to make calls work
between
VoIP phones connected to PBX and UEs connected to Osmocom system. I've
tried two
PBXs: Kamailio with rtpengine and Asterisk. Signalling worked good between
VoIP
phone and UE with both PBXs; calls between two UEs registered on Osmocom
system
worked good also... But I fail to do transcoding (calls between VoIP phone
and
UE). The problem is that it is unknown which codec is used by nano3g
ip.access
femtocell.
So, the question is: Do you know what codecs were used for speech in your
setup
with nano3g ip.access femtocells? Or do you know how to find out that
information? (It was stated by ip.access that they use AMR but I failed to
match
AMR specs with RTP payload that was sent by femtocell...).
I would be very grateful for any ideas.
Kind regards, Mykola
--
Best Regards,
Sandi