[asterisk-users] Incoming calls get 488 error

[Technical Support]

I got a new SNOM M65 which works fine for outgoing calls, but incoming 
calls never ring at the handset.  I captured the SIP traffic and see 
that my M65 is replying with an "488 not acceptable here".  From what I 
read this is usually codec related but both asterisk and the M65 are set 
for ulaw as first choice.

I have a SIP trace below.  Can someone suggest why the 488 is being 
generated?

-----------------------------------

Received from udp:192.168.253.4:5060 at 21/08/2015 18:37:00  (1198 bytes)

INVITE sip:290006 at 192.168.253.20;line=14994 SIP/2.0
Via: SIP/2.0/UDP 192.168.253.4:5060;branch=z9hG4bK4990095a
Max-Forwards: 70
From: "test user" <sip:230 at 192.168.253.4>;tag=as7b616c8d
To: <sip:290006 at 192.168.253.20;line=14994>
Contact: <sip:230 at 192.168.253.4:5060>
Call-ID: 36334383058109cd2325341a0f18ac79 at 192.168.253.4:5060
CSeq: 102 INVITE
User-Agent: FPBX-2.11.0(11.10.2)
Date: Fri, 21 Aug 2015 22:37:02 GMT
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY, 
INFO, PUBLISH, MESSAGE
Supported: replaces, timer
Content-Type: application/sdp
Content-Length: 606

v=0
o=root 1678280845 1678280845 IN IP4 192.168.253.4
s=Asterisk PBX 11.10.2
c=IN IP4 192.168.253.4
b=CT:384
t=0 0
m=audio 18090 RTP/AVP 0 8 101
a=rtpmap:0 PCMU/8000
a=rtpmap:8 PCMA/8000
a=rtpmap:101 telephone-event/8000
a=fmtp:101 0-16
a=ptime:20
a=sendrecv
m=video 12226 RTP/AVP 99 98 34 31
a=rtpmap:99 H264/90000
a=fmtp:99 
redundant-pic-cap=0;parameter-add=0;packetization-mode=0;level-asymmetry-allowed=0
a=rtpmap:98 H263-1998/90000
a=fmtp:98 F=0;I=0;J=0;T=0;K=0;N=0;BPP=0;HRD=0
a=rtpmap:34 H263/90000
a=fmtp:34 F=0;I=0;J=0;T=0;K=0;N=0;BPP=0;HRD=0
a=rtpmap:31 H261/90000
a=sendrecv


Sent to udp:192.168.253.4:5060 at 21/08/2015 18:37:00  (280 bytes)

SIP/2.0 100 Trying
Via: SIP/2.0/UDP 192.168.253.4:5060;branch=z9hG4bK4990095a
From: "test user" <sip:230 at 192.168.253.4>;tag=as7b616c8d
To: <sip:290006 at 192.168.253.20;line=14994>
Call-ID: 36334383058109cd2325341a0f18ac79 at 192.168.253.4:5060
CSeq: 102 INVITE
Content-Length: 0



Sent to udp:192.168.253.4:5060 at 21/08/2015 18:37:00  (441 bytes)

SIP/2.0 488 Not Acceptable Here
Via: SIP/2.0/UDP 192.168.253.4:5060;branch=z9hG4bK4990095a
Max-Forwards: 70
From: "test user" <sip:230 at 192.168.253.4>;tag=as7b616c8d
To: <sip:290006 at 192.168.253.20;line=14994>;tag=ld65q
Call-ID: 36334383058109cd2325341a0f18ac79 at 192.168.253.4:5060
CSeq: 102 INVITE
Contact: <sip:290006 at 192.168.253.20;line=14994>
User-Agent: snomM700/03.24.0007 (MAC=0004136103FB; SER= 00000; HW=255)
Content-Length: 0