Random problem with call from queues

We’ve elastix 2.0 with Asterisk 1.6.2.13.
One queue(11) with 4 static agents (extensions:1001, 1002,1003 and (1004 not registered at this time)).
PBX and extensions(sip phones) are in same network and between them is nothing besides one switch (no routing, no switch, no NAT and etc).
Generally everything is working fine, but randomly, calls from queue do not reach the agents, same time the direct calls to agent extensions (without queue) works.
Restarting amportal somtimes helps, somtimes not.
command “core show channels” shows channel state down.
command “queue show 11” - agent (In use), but agent phon is not ringing.
On tcpdump server is retransmitting INVITE packets.
Extensions (tested on xlite) received this INVITEs, but did not react, they did not send 100 TRYING. After examining INVITE packets we found that sip from address (sip.from.addr) is missing. Same on sip debug.

core show channels Channel Location State Application(Data) SIP/1001-00000087 1001@unlimited:1 Down AppDial((Outgoing Line)) SIP/1002-00000086 1002@unlimited:1 Down AppDial((Outgoing Line)) SIP/1003-00000085 1003@unlimited:1 Down AppDial((Outgoing Line)) Local/1001@from-queu s@macro-dial:7 Ring Dial(SIP/1001,,trM(auto-blkvm) Local/1001@from-queu 11@from-queue:1 Ringing AppQueue((Outgoing Line)) Local/1002@from-queu s@macro-dial:7 Ring Dial(SIP/1002,,trM(auto-blkvm) Local/1002@from-queu 11@from-queue:1 Ringing AppQueue((Outgoing Line)) Local/1003@from-queu s@macro-dial:7 Ring Dial(SIP/1003,,trM(auto-blkvm) Local/1003@from-queu 11@from-queue:1 Ringing AppQueue((Outgoing Line)) SIP/morA-00000084 s@ivr-37:12 Up BackGround(custom/neww220-35-3 SIP/morA-00000083 s@ivr-37:12 Up BackGround(custom/neww220-35-3 SIP/morA-0000007c 11@ext-queues:10 Up Queue(11,t,,) SIP/morA-00000072 11@ext-queues:10 Up Queue(11,t,,) SIP/morA-0000006e 11@ext-queues:10 Up Queue(11,t,,) SIP/morA-0000004d 11@ext-queues:10 Up Queue(11,t,,) SIP/morA-0000002b 11@ext-queues:10 Up Queue(11,t,,) SIP/morA-0000000e 11@ext-queues:10 Up Queue(11,t,,) SIP/morA-00000005 11@ext-queues:10 Up Queue(11,t,,) 18 active channels 12 active calls 171 calls processed

queue show 11 11 has 7 calls (max unlimited) in 'ringall' strategy (1s holdtime, 5s talktime), W:0, C:1, A:9, SL:100.0% within 60s Members: Local/1004@from-queue/n (Not in use) has taken no calls yet Local/1001@from-queue/n (In use) has taken 1 calls (last was 706 secs ago) Local/1002@from-queue/n (In use) has taken no calls yet Local/1003@from-queue/n (In use) has taken no calls yet Callers: 1. SIP/morA-00000005 (wait: 12:05, prio: 0) 2. SIP/morA-0000000e (wait: 11:30, prio: 0) 3. SIP/morA-0000002b (wait: 8:33, prio: 0) 4. SIP/morA-0000004d (wait: 4:55, prio: 0) 5. SIP/morA-0000006e (wait: 1:56, prio: 0) 6. SIP/morA-00000072 (wait: 1:20, prio: 0) 7. SIP/morA-0000007c (wait: 0:24, prio: 0)

from sip debug:
Retransmitting #3 (no NAT) to 192.1.1.198:5060:
INVITE sip:1002@192.1.1.198:5060 SIP/2.0
Via: SIP/2.0/UDP 192.1.1.254:5060;branch=z9hG4bK1864846d;rport
Max-Forwards: 70
From: "" sip:XXXX@192.1.1.254;tag=as7c922bdf
To: sip:1002@192.1.1.198:5060
Contact: sip:XXXX@192.1.1.254
Call-ID: 6d5a8b412a3914b3382e49527faeb6c8@192.1.1.254
CSeq: 102 INVITE
User-Agent: Asterisk PBX 1.6.2.13
Date: Wed, 17 Feb 2016 07:20:16 GMT
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY, INFO
Supported: replaces, timer
Content-Type: application/sdp
Content-Length: 282

tail -n 50 /var/log/asterisk/queue_log 1455694828|1455694408.245|11|NONE|ABANDON|3|8|394 1455694832|1455693978.5|11|Local/1004@from-queue/n|RINGNOANSWER|0 1455694845|1455693978.5|11|Local/1001@from-queue/n|RINGNOANSWER|13000 1455694845|1455693978.5|11|Local/1003@from-queue/n|RINGNOANSWER|13000 1455694845|1455693978.5|11|Local/1002@from-queue/n|RINGNOANSWER|13000 1455694850|1455693978.5|11|Local/1004@from-queue/n|RINGNOANSWER|0 1455694863|1455693978.5|11|Local/1001@from-queue/n|RINGNOANSWER|13000 1455694863|1455693978.5|11|Local/1002@from-queue/n|RINGNOANSWER|13000 1455694863|1455693978.5|11|Local/1003@from-queue/n|RINGNOANSWER|13000 1455694874|1455693978.5|11|Local/1004@from-queue/n|RINGNOANSWER|1000 1455694874|1455694711.419|11|NONE|ABANDON|5|7|137 1455694886|1455693978.5|11|Local/1003@from-queue/n|RINGNOANSWER|13000 1455694886|1455693978.5|11|Local/1002@from-queue/n|RINGNOANSWER|13000 1455694886|1455693978.5|11|Local/1001@from-queue/n|RINGNOANSWER|13000 1455694889|1455694839.493|11|NONE|ENTERQUEUE||XXXX 1455694892|1455693978.5|11|Local/1004@from-queue/n|RINGNOANSWER|0 1455694905|1455693978.5|11|Local/1003@from-queue/n|RINGNOANSWER|13000 1455694905|1455693978.5|11|Local/1002@from-queue/n|RINGNOANSWER|13000 1455694905|1455693978.5|11|Local/1001@from-queue/n|RINGNOANSWER|13000 1455694909|1455694883.521|11|NONE|ENTERQUEUE||XXXX 1455694912|1455694864.507|11|NONE|ENTERQUEUE||XXXX 1455694915|1455693978.5|11|Local/1004@from-queue/n|RINGNOANSWER|0 1455694917|1455694190.131|11|NONE|ABANDON|2|5|701 1455694922|1455694896.535|11|NONE|ENTERQUEUE||XXXX 1455694926|1455694900.536|11|NONE|ENTERQUEUE||XXXX 1455694928|1455693978.5|11|Local/1002@from-queue/n|RINGNOANSWER|13000 1455694928|1455693978.5|11|Local/1003@from-queue/n|RINGNOANSWER|13000 1455694928|1455693978.5|11|Local/1001@from-queue/n|RINGNOANSWER|13000 1455694933|1455693978.5|11|Local/1004@from-queue/n|RINGNOANSWER|0 1455694946|1455693978.5|11|Local/1002@from-queue/n|RINGNOANSWER|13000 1455694946|1455693978.5|11|Local/1003@from-queue/n|RINGNOANSWER|13000 1455694946|1455693978.5|11|Local/1001@from-queue/n|RINGNOANSWER|13000 1455694956|1455693978.5|11|Local/1004@from-queue/n|RINGNOANSWER|0 1455694969|1455693978.5|11|Local/1001@from-queue/n|RINGNOANSWER|13000 1455694969|1455693978.5|11|Local/1002@from-queue/n|RINGNOANSWER|13000 1455694969|1455693978.5|11|Local/1003@from-queue/n|RINGNOANSWER|13000 1455694975|1455693978.5|11|Local/1004@from-queue/n|RINGNOANSWER|1000 1455694987|1455693978.5|11|Local/1001@from-queue/n|RINGNOANSWER|13000 1455694987|1455693978.5|11|Local/1003@from-queue/n|RINGNOANSWER|13000 1455694987|1455693978.5|11|Local/1002@from-queue/n|RINGNOANSWER|13000 1455694998|1455693978.5|11|Local/1004@from-queue/n|RINGNOANSWER|0 1455695000|1455694974.570|11|NONE|ENTERQUEUE||XXXX 1455695010|1455693978.5|11|Local/1003@from-queue/n|RINGNOANSWER|12000 1455695010|1455693978.5|11|Local/1002@from-queue/n|RINGNOANSWER|12000 1455695010|1455693978.5|11|Local/1001@from-queue/n|RINGNOANSWER|12000 1455695016|1455693978.5|11|Local/1004@from-queue/n|RINGNOANSWER|0 1455695029|1455693978.5|11|Local/1003@from-queue/n|RINGNOANSWER|13000 1455695029|1455693978.5|11|Local/1002@from-queue/n|RINGNOANSWER|13000 1455695029|1455693978.5|11|Local/1001@from-queue/n|RINGNOANSWER|13000 1455695030|1455694896.535|11|NONE|ABANDON|8|8|108

The version of Asterisk you are using is long since unsupported, so my memory of that era of any potential issues that would exhibit those symptoms is cloudy at best. Nothing comes to mind in recent versions though of someone having such a problem with chan_sip.

Also, amportal is not part of Asterisk.

SOLVED! it was problem from VOIP Provider.

Dear Fropa,

I need your help i am facing the same problem this time and i have same asterisk 1.6.2.22 version.
I have also no any switch, router, NAT issue this is on the same network and same suddenly no call reach to agent from the queue then same core channels queue etc,stop start asterisk and again start fine but same suddenly calls not landed to agents from the queue and i have same SIP provider i have also SIP trunk and i am sure this is also my SIP Provider issue but i am not able to justify how can i do this and i can say to SIP provider that what setting they need to check or change.
Please help me to solve my problem.