Многоканальный телефон для приёма звонков

Помогите балбесу понять. Есть два офиса где стоят хард АТС в одном "Panasonic TDA-100" в другом "samsung officeserv 7200" в каждом из офисов стоит астериск который соединен с АТС по Е1 каналу. астериски в свою очередь соединены по IAX2 транку. Настроено так что абоненты в офисах звонят друг-другу по внутренним номерам 1ХХ и 3ХХ. В одном офисе секретарь 101 а в другом 301 и если я звоню из диапазона 1ХХ секретарю 301 то дозванивается только первый позвонивший а второй если наберет то уже не сможет дозвониться а должен висеть как вторая линия. Что я не так делаю почему так?

звоню в другой офис так:

exten => _3XX,1,Dial(IAX2/officeSpb/${EXTEN})

лог звонка:
    -- Accepting call from '122' to '301' on channel 0/3, span 1
    -- Executing [301@from-internal:1] Dial("DAHDI/3-1", "IAX2/officeSpb/301") in new stack
    -- Called officeSpb/301
    -- Call accepted by 192.168.1.11 (format g729)
    -- Format for call is g729
    -- IAX2/officeSpb-1510 is ringing
    -- IAX2/officeSpb-1510 answered DAHDI/3-1
    -- Accepting call from '121' to '301' on channel 0/4, span 1
    -- Executing [301@from-internal:1] Dial("DAHDI/4-1", "IAX2/officeSpb/301") in new stack
    -- Called officeSpb/301
    -- Call accepted by 192.168.1.11 (format g729)
    -- Format for call is g729
    -- IAX2/officeSpb-10514 is making progress passing it to DAHDI/4-1
    -- IAX2/officeSpb-10514 is circuit-busy
    -- Hungup 'IAX2/officeSpb-10514'
  == Everyone is busy/congested at this time (1:0/1/0)
    -- Executing [301@from-internal:4] Hangup("DAHDI/4-1", "") in new stack
  == Spawn extension (from-internal, 301, 4) exited non-zero on 'DAHDI/4-1'
    -- Executing [h@from-internal:1] Macro("DAHDI/4-1", "hangupcall") in new stack
    -- Executing [s@macro-hangupcall:1] GotoIf("DAHDI/4-1", "1?noautomon") in new stack
    -- Goto (macro-hangupcall,s,3)
    -- Executing [s@macro-hangupcall:3] NoOp("DAHDI/4-1", "TOUCH_MONITOR_OUTPUT=") in new stack
    -- Executing [s@macro-hangupcall:4] GotoIf("DAHDI/4-1", "1?skiprg") in new stack
    -- Goto (macro-hangupcall,s,7)
    -- Executing [s@macro-hangupcall:7] GotoIf("DAHDI/4-1", "1?skipblkvm") in new stack
    -- Goto (macro-hangupcall,s,10)
    -- Executing [s@macro-hangupcall:10] GotoIf("DAHDI/4-1", "1?theend") in new stack
    -- Goto (macro-hangupcall,s,12)
    -- Executing [s@macro-hangupcall:12] Hangup("DAHDI/4-1", "") in new stack
  == Spawn extension (macro-hangupcall, s, 12) exited non-zero on 'DAHDI/4-1' in macro 'hangupcall'
  == Spawn extension (from-internal, h, 1) exited non-zero on 'DAHDI/4-1'
    -- Hungup 'DAHDI/4-1'

На принимающем астериске:
 -- Accepting UNAUTHENTICATED call from 192.168.9.50:
       > requested format = g729,
       > requested prefs = (g729),
       > actual format = g729,
       > host prefs = (g729),
       > priority = mine
    -- Executing [301@from-internal:1] Dial("IAX2/officeMsk-434", "Dahdi/g1/301,,tTw") in new stack
    -- Requested transfer capability: 0x00 - SPEECH
    -- Called g1/301
    -- DAHDI/2-1 is ringing
    -- DAHDI/2-1 answered IAX2/officeMsk-434
    -- Accepting UNAUTHENTICATED call from 192.168.9.50:
       > requested format = g729,
       > requested prefs = (g729),
       > actual format = g729,
       > host prefs = (g729),
       > priority = mine
    -- Executing [301@from-internal:1] Dial("IAX2/officeMsk-974", "Dahdi/g1/301,,tTw") in new stack
    -- Requested transfer capability: 0x00 - SPEECH
    -- Called g1/301
    -- Channel 0/3, span 1 got hangup request, cause 17
    -- DAHDI/3-1 is busy
    -- Hungup 'DAHDI/3-1'
  == Everyone is busy/congested at this time (1:1/0/0)
    -- Executing [301@from-internal:2] NoCDR("IAX2/officeMsk-974", "") in new stack
    -- Executing [301@from-internal:3] Progress("IAX2/officeMsk-974", "") in new stack
    -- Executing [301@from-internal:4] Wait("IAX2/officeMsk-974", "1") in new stack
    -- Executing [301@from-internal:5] Playback("IAX2/officeMsk-974", "silence/1&cannot-complete-as-dialed&check-number-dial-again,noanswer") in new stack
    -- <IAX2/officeMsk-974> Playing 'silence/1.gsm' (language 'en')
    -- <IAX2/officeMsk-974> Playing 'cannot-complete-as-dialed.gsm' (language 'en')
    -- <IAX2/officeMsk-974> Playing 'check-number-dial-again.gsm' (language 'en')
    -- Executing [301@from-internal:6] Wait("IAX2/officeMsk-974", "1") in new stack
    -- Executing [301@from-internal:7] Congestion("IAX2/officeMsk-974", "20") in new stack
  == Spawn extension (from-internal, 301, 7) exited non-zero on 'IAX2/officeMsk-974'
    -- Executing [h@from-internal:1] Macro("IAX2/officeMsk-974", "hangupcall") in new stack
    -- Executing [s@macro-hangupcall:1] GotoIf("IAX2/officeMsk-974", "1?noautomon") in new stack
    -- Goto (macro-hangupcall,s,3)
    -- Executing [s@macro-hangupcall:3] NoOp("IAX2/officeMsk-974", "TOUCH_MONITOR_OUTPUT=") in new stack
    -- Executing [s@macro-hangupcall:4] GotoIf("IAX2/officeMsk-974", "1?skiprg") in new stack
    -- Goto (macro-hangupcall,s,7)
    -- Executing [s@macro-hangupcall:7] GotoIf("IAX2/officeMsk-974", "1?skipblkvm") in new stack
    -- Goto (macro-hangupcall,s,10)
    -- Executing [s@macro-hangupcall:10] GotoIf("IAX2/officeMsk-974", "1?theend") in new stack
    -- Goto (macro-hangupcall,s,12)
    -- Executing [s@macro-hangupcall:12] Hangup("IAX2/officeMsk-974", "") in new stack
  == Spawn extension (macro-hangupcall, s, 12) exited non-zero on 'IAX2/officeMsk-974' in macro 'hangupcall'
  == Spawn extension (from-internal, h, 1) exited non-zero on 'IAX2/officeMsk-974'