pjsip.conf:
[simpletrans]
type=transport
protocol=udp
bind=0.0.0.0
local_net = 172.31.17.106/20 #Internal IP of Server
external_media_address = 54.214.106.62 #External Address of Server
external_signaling_address = 54.214.106.62

pjsip_wizard.conf:
[my-itsp]
type = wizard
transport = simpletrans
sends_auth = yes
sends_registrations = yes
remote_hosts = itsp.host
endpoint/allow = ulaw
outbound_auth/username = username
outbound_auth/password = password
endpoint/context = default
endpoint/direct_media = no
aor/qualify_frequency = 15
hint_context = Hints
hint_application = Dial(${HINT})


[user_defaults](!)
type = wizard
transport = simpletrans
accepts_registrations = yes
sends_registrations = no
accepts_auth = yes
sends_auth = no
has_hint = yes
hint_context = internal
hint_application = Dial(${HINT})
endpoint/context = internal
endpoint/allow_subscribe = yes
endpoint/allow = !all,ulaw,gsm,g722
endpoint/direct_media = no
endpoint/force_rport = yes
endpoint/disable_direct_media_on_nat = yes
endpoint/direct_media_method = invite
endpoint/ice_support = yes
endpoint/moh_suggest = default
endpoint/send_rpid = yes
endpoint/rewrite_contact = yes
endpoint/rtp_symmetric = yes
endpoint/send_pai = yes
endpoint/allow_transfer = yes
endpoint/trust_id_inbound = yes
endpoint/device_state_busy_at = 1
endpoint/trust_id_outbound = yes
endpoint/send_diversion = yes
aor/qualify_frequency = 30
aor/authenticate_qualify = no
aor/max_contacts = 1
aor/remove_existing = yes
aor/minimum_expiration = 30
aor/support_path = yes
phoneprov/PROFILE = profile1


[1000](user_defaults)
hint_exten = 1000
inbound_auth/username = bob
inbound_auth/password = password

Console output for call:
  == Setting global variable 'SIPDOMAIN' to '54.214.106.62'
    -- Executing [9@internal:1] Answer("PJSIP/1000-00000001", "") in new stack
       > 0x7fc4102fadd0 -- Strict RTP learning after remote address set to: 192.168.254.148:40024
    -- Executing [9@internal:2] Echo("PJSIP/1000-00000001", "") in new stack
  == Spawn extension (internal, 9, 2) exited non-zero on 'PJSIP/1000-00000001'