Jul  6 11:27:32 WARNING[1019]: chan_unicall.c:2644 handle_uc_event: Unicall/1 event Protocol failure
    -- Unicall/1 protocol error. Cause 32773
    -- Hungup 'UniCall/1-1'
  == Spawn extension (1000, 97622860, 1) exited non-zero on 'SIP/1000-081a8878'
    -- Incoming call: Got SIP response 500 "Internal Server Error" back from 10.11.177.58
    -- Executing Dial("SIP/1000-081a8878", "Unicall/g1/0318433121212") in new stack
    -- Called g1/0318433121212
Jul  6 11:28:07 WARNING[1068]: chan_unicall.c:2644 handle_uc_event: Unicall/1 event Dialing
Jul  6 11:28:12 WARNING[1068]: chan_unicall.c:2644 handle_uc_event: Unicall/1 event Protocol failure
    -- Unicall/1 protocol error. Cause 32772
Jul  6 11:28:12 WARNING[1068]: app_dial.c:714 wait_for_answer: Unable to forward voice
    -- Hungup 'UniCall/1-1'
  == Everyone is busy/congested at this time (1:0/0/1)
    -- Executing Goto("SIP/1000-081a8878", "1-CHANUNAVAIL|1") in new stack
    -- Goto (1000,1-CHANUNAVAIL,1)
Jul  6 11:28:12 WARNING[1068]: pbx.c:1700 pbx_extension_helper: No application 'Playtone' for extension (1000, 1-CHANUNAVAIL, 1)
  == Spawn extension (1000, 1-CHANUNAVAIL, 1) exited non-zero on 'SIP/1000-081a8878'
Jul  6 11:29:23 WARNING[803]: res_musiconhold.c:422 spawn_mp3: Found no files in '/var/lib/asterisk/mohmp3'
Jul  6 11:29:23 WARNING[803]: res_musiconhold.c:504 monmp3thread: Unable to spawn mp3player