diff --git a/app/vars/app_defaults.php b/app/vars/app_defaults.php
index b7f5adfcf6..af2c44893c 100644
--- a/app/vars/app_defaults.php
+++ b/app/vars/app_defaults.php
@@ -35,8 +35,8 @@ $vars_string = <<<EOD
 {"var_name":"xmpp_client_profile","var_value":"xmppc","var_cat":"Dingaling","var_enabled":"true","var_description":"eG1wcF9jbGllbnRfcHJvZmlsZSBhbmQgeG1wcF9zZXJ2ZXJfcHJvZmlsZSB4bXBwX2NsaWVudF9wcm9maWxlIGNhbiBiZSBhbnkgc3RyaW5nLiB4bXBwX3NlcnZlcl9wcm9maWxlIGlzIGFwcGVuZGVkIHRvICJkaW5nYWxpbmdfIiB0byBmb3JtIHRoZSBkYXRhYmFzZSBuYW1lIGNvbnRhaW5pbmcgdGhlICJzdWJzY3JpcHRpb25zIiB0YWJsZS4gdXNlZCBieTogZGluZ2FsaW5nLmNvbmYueG1sIGVudW0uY29uZi54bWw="},
 {"var_name":"xmpp_server_profile","var_value":"xmpps","var_cat":"Dingaling","var_enabled":"true","var_description":""},
 {"var_name":"bind_server_ip","var_value":"auto","var_cat":"Dingaling","var_enabled":"true","var_description":"Q2FuIGJlIGFuIGlwIGFkZHJlc3MsIGEgZG5zIG5hbWUsIG9yICJhdXRvIi4gVGhpcyBkZXRlcm1pbmVzIGFuIGlwIGFkZHJlc3MgYXZhaWxhYmxlIG9uIHRoaXMgaG9zdCB0byBiaW5kLiBJZiB5b3UgYXJlIHNlcGFyYXRpbmcgUlRQIGFuZCBTSVAgdHJhZmZpYywgeW91IHdpbGwgd2FudCB0byBoYXZlIHVzZSBkaWZmZXJlbnQgYWRkcmVzc2VzIHdoZXJlIHRoaXMgdmFyaWFibGUgYXBwZWFycy4gVXNlZCBieTogZGluZ2FsaW5nLmNvbmYueG1s"},
-{"var_name":"external_rtp_ip","var_value":"auto-nat","var_cat":"IP Address","var_enabled":"true","var_description":"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"},
-{"var_name":"external_sip_ip","var_value":"auto-nat","var_cat":"IP Address","var_enabled":"true","var_description":"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"},
+{"var_name":"external_rtp_ip","var_value":"\$\${local_ip_v4}","var_cat":"IP Address","var_enabled":"true","var_description":"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"},
+{"var_name":"external_sip_ip","var_value":"\$\${local_ip_v4}","var_cat":"IP Address","var_enabled":"true","var_description":"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"},
 {"var_name":"unroll_loops","var_value":"true","var_cat":"SIP","var_enabled":"true","var_description":"VXNlZCB0byB0dXJuIG9uIHNpcCBsb29wYmFjayB1bnJvbGxpbmcu"},
 {"var_name":"call_debug","var_value":"false","var_cat":"Defaults","var_enabled":"true","var_description":""},
 {"var_name":"console_loglevel","var_value":"info","var_cat":"Defaults","var_enabled":"true","var_description":""},