-- Attempting call on CAPI/ISDN4/3488866859 for 1@sendfax:1 (Retry 1)
Dec 30 13:28:43 NOTICE[23631]: channel.c:2416 __ast_request_and_dial: Don't know what to do with control frame 15
  == ISDN4: Setting up echo canceller (PLCI=0x204, function=1, options=4, tail=64)
  == ISDN4: Setting up DTMF detector (PLCI=0x204, flag=1)
       > Channel CAPI/ISDN4/3488866859-38 was answered.
  == Starting CAPI/ISDN4/3488866859-38 at sendfax,1,1 failed so falling back to exten 's'
    -- Executing Wait("CAPI/ISDN4/3488866859-38", "3") in new stack
    -- ISDN4: Error setting up echo canceller (PLCI=0x204)
Dec 30 13:28:49 WARNING[18722]: chan_capi.c:3334 show_capi_conf_error: ISDN4: conf_error 0x300b PLCI=0x204 Command=FACILITY_CONF,0x8497
       > CAPI INFO 0x300b: Facility not supported
    -- Executing SayDigits("CAPI/ISDN4/3488866859-38", "123456") in new stack
    -- Playing 'digits/1' (language 'en')
    -- Playing 'digits/2' (language 'en')
    -- Playing 'digits/3' (language 'en')
    -- Attempting call on CAPI/ISDN4/3488866859 for 1@sendfax:1 (Retry 1)
Dec 30 13:28:54 NOTICE[23639]: channel.c:2416 __ast_request_and_dial: Don't know what to do with control frame 15
    -- Playing 'digits/4' (language 'en')
    -- Playing 'digits/5' (language 'en')
    -- Playing 'digits/6' (language 'en')
    -- Executing Hangup("CAPI/ISDN4/3488866859-38", "") in new stack
  == Spawn extension (sendfax, s, 3) exited non-zero on 'CAPI/ISDN4/3488866859-38'
  == ISDN4: CAPI Hangingup
Dec 30 13:28:56 NOTICE[23631]: pbx_spool.c:280 attempt_thread: Call completed to CAPI/ISDN4/3488866859
       > CAPI INFO 0x3490: Normal call clearing
  == ISDN4: Setting up echo canceller (PLCI=0x304, function=1, options=4, tail=64)
  == ISDN4: Setting up DTMF detector (PLCI=0x304, flag=1)
       > Channel CAPI/ISDN4/3488866859-39 was answered.
  == Starting CAPI/ISDN4/3488866859-39 at sendfax,1,1 failed so falling back to exten 's'
    -- Executing Wait("CAPI/ISDN4/3488866859-39", "3") in new stack
    -- ISDN4: Error setting up echo canceller (PLCI=0x304)
Dec 30 13:29:01 WARNING[18722]: chan_capi.c:3334 show_capi_conf_error: ISDN4: conf_error 0x300b PLCI=0x304 Command=FACILITY_CONF,0x8497
       > CAPI INFO 0x300b: Facility not supported
    -- Executing SayDigits("CAPI/ISDN4/3488866859-39", "123456") in new stack
    -- Playing 'digits/1' (language 'en')
    -- Playing 'digits/2' (language 'en')
    -- Playing 'digits/3' (language 'en')
    -- Playing 'digits/4' (language 'en')
    -- Playing 'digits/5' (language 'en')
    -- Playing 'digits/6' (language 'en')
    -- Executing Hangup("CAPI/ISDN4/3488866859-39", "") in new stack
  == Spawn extension (sendfax, s, 3) exited non-zero on 'CAPI/ISDN4/3488866859-39'
  == ISDN4: CAPI Hangingup
Dec 30 13:29:07 NOTICE[23639]: pbx_spool.c:280 attempt_thread: Call completed to CAPI/ISDN4/3488866859
       > CAPI INFO 0x3490: Normal call clearing