Aug 10 18:34:29 NOTICE[27220]: channel.c:1703 ast_set_write_format: Unable to find a path from slin to g729
Aug 10 18:34:29 WARNING[27220]: indications.c:77 playtones_alloc: Unable to set 'SIP/6250000402-cee3' to signed linear format (write)
    -- Got SIP response 486 "busy" back from 192.168.2.29
    -- SIP/200-5da2 is busy
    -- SIP/201-b879 is ringing
Aug 10 18:34:29 NOTICE[27220]: channel.c:1703 ast_set_write_format: Unable to find a path from slin to g729
Aug 10 18:34:29 WARNING[27220]: indications.c:77 playtones_alloc: Unable to set 'SIP/6250000402-cee3' to signed linear format (write)
    -- SIP/202-127b is ringing
    -- SIP/tzm1-0963 answered SIP/200-f59f
    -- Attempting native bridge of SIP/200-f59f and SIP/tzm1-0963
  == Spawn extension (default, 0302060311, 1) exited non-zero on 'SIP/200-f59f'
  == Spawn extension (inbound, s, 2) exited non-zero on 'SIP/6250000402-cee3'