SIP/2.0 401 Unauthorized

Доброго дня! Прошу помощи! У оператора какая-то особая железка, на которой зарегистрироваться удалось только в описанном формате, но звонки при этом не проходят. В консоль астер ничего не отсыпает, снял дампом.

sip.conf:

[general]
subscribemwi=no
language=ru
nat=no
format=wav
videosupport=yes
dtmfmode=auto
relaxdtmf=yes
limitonpeers=yes
bindaddr=0.0.0.0
rtpkeepalive=5
limitonpeer=yes
bindport=5060
allowguest=no
alwaysauthreject=yes
accept_outofcall_message=yes
outofcall_message_context=messages
auth_message_requests=no
textsupport=yes

register => 74952780526$abc.ru:Passwd:74952780526@sip.abc.ru



[74952780526]
type=friend
;defaultuser=74952780526$abc.ru
;secret=Passwd
;fromuser=74952780526$abc.ru
host=sip.abc.ru
nat=no
context=incoming
insecure=invite
qualify=yes
externrefresh=60
allow=all

tcpdump:

10:04:25.983254 IP (tos 0x0, ttl 62, id 16229, offset 0, flags [DF], proto UDP (17), length 1407)
    109.167.231.150.5061 > 109.167.231.118.5060: SIP, length: 1379
        INVITE sip:s@109.167.231.118:5060 SIP/2.0
        Via: SIP/2.0/UDP 109.167.231.150:5061;rport;branch=z9hG4bK-3568932602-3910231029-67170980-3977954595
        From: <sip:74991123007@109.167.231.150:5061;user=phone>;tag=3523646202-3910231029-67170980-3977954595
        To: <sip:74952780526$abc.ru@sip.abc.ru>
        Call-ID: 8EF23D13E2DC6D9957E662550AF0154B
        CSeq: 1 INVITE
        Contact: <sip:74991123007@109.167.231.150:5061;user=phone>
        Content-Type: application/sdp
        Allow: ACK, BYE, CANCEL, INFO, INVITE, OPTIONS, REFER, REGISTER, SUBSCRIBE, UPDATE
        Max-Forwards: 70
        User-Agent: TS-v4.5.1-20g
        Cisco-Guid: 4201734282-4116910569-2767323140-600120045
        Content-Length:   741

        v=0
        o=- 1571814265 1571814265 IN IP4 109.167.231.150
        s=-
        c=IN IP4 109.167.231.150
        t=0 0
        m=audio 14414 RTP/AVP 8 0 18 4 3 102 103 104 105 110 111 112 106 101
        a=rtpmap:8 PCMA/8000
        a=rtpmap:0 PCMU/8000
        a=rtpmap:18 G729/8000
        a=fmtp:18 annexb=no
        a=rtpmap:4 G723/8000
        a=fmtp:4 annexa=yes
        a=rtpmap:3 gsm/8000
        a=rtpmap:102 speex/8000
        a=fmtp:102 mode=3;vbr=off
        a=rtpmap:103 iLBC/8000
        a=fmtp:103 mode=30
        a=rtpmap:104 iLBC/8000
        a=fmtp:104 mode=20
        a=rtpmap:105 AMR/8000
        a=fmtp:105 mode-set=0,1,2,3,4,5,6,7
        a=rtpmap:110 G726-40/8000
        a=rtpmap:111 G722/8000
        a=rtpmap:112 G7221/16000
        a=fmtp:112 bitrate=32000
        a=rtpmap:106 AMR-WB/8000
        a=fmtp:106 mode-set=0,1,2,3,4,5,6,7,8
        a=rtpmap:101 telephone-event/8000
        a=fmtp:101 0-15
        a=sendrecv
10:04:25.984415 IP (tos 0x0, ttl 64, id 6229, offset 0, flags [none], proto UDP (17), length 642)
    109.167.231.118.5060 > 109.167.231.150.5061: SIP, length: 614
        SIP/2.0 401 Unauthorized
        Via: SIP/2.0/UDP 109.167.231.150:5061;branch=z9hG4bK-3568932602-3910231029-67170980-3977954595;received=109.167.231.150;rport=5061
        From: <sip:74991123007@109.167.231.150:5061;user=phone>;tag=3523646202-3910231029-67170980-3977954595
        To: <sip:74952780526$abc.ru@sip.abc.ru>;tag=as42e7b6b6
        Call-ID: 8EF23D13E2DC6D9957E662550AF0154B
        CSeq: 1 INVITE
        Server: Asterisk PBX 11.25.1
        Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY, INFO, PUBLISH, MESSAGE
        Supported: replaces, timer
        WWW-Authenticate: Digest algorithm=MD5, realm="asterisk", nonce="086c945e"
        Content-Length: 0

10:04:25.987596 IP (tos 0x0, ttl 62, id 16230, offset 0, flags [DF], proto UDP (17), length 443)
    109.167.231.150.5061 > 109.167.231.118.5060: SIP, length: 415
        ACK sip:s@109.167.231.118:5060 SIP/2.0
        Via: SIP/2.0/UDP 109.167.231.150:5061;rport;branch=z9hG4bK-3568932602-3910231029-67170980-3977954595
        From: <sip:74991123007@109.167.231.150:5061;user=phone>;tag=3523646202-3910231029-67170980-3977954595
        To: <sip:74952780526$abc.ru@sip.abc.ru>;tag=as42e7b6b6
        Call-ID: 8EF23D13E2DC6D9957E662550AF0154B
        CSeq: 1 ACK
        Max-Forwards: 70
        User-Agent: TS-v4.5.1-20g
        Content-Length: 0

5 packets captured
5 packets received by filter
0 packets dropped by kernel