diff --git a/assets/js/sccp_manager.js b/assets/js/sccp_manager.js
index 6c3b326..1fffeb4 100644
--- a/assets/js/sccp_manager.js
+++ b/assets/js/sccp_manager.js
@@ -214,12 +214,19 @@ $(document).ready(function () {
         e.preventDefault();
     });
 
-    $('#sccp_hw_mac').change(function() {
+    $('#sccp_hw_mac').focus();
+
+    $('#sccp_hw_mac').focusout(function() {
         var value = $(this).val();
         const regex = new RegExp('^([0-9A-Fa-f]{2}[:.-]?){5}([0-9A-Fa-f]{2})$');
         if ( regex.test(value) === false ) {
+            $('#ajaxsubmit2').attr('disabled', 'disabled');
+            $('#ajaxsubmit').attr('disabled', 'disabled');
             fpbxToast(_('Invalid Mac Address'),_('Invalid Mac Address'), 'warning');
-            setTimeout(function(){document.getElementById("sccp_hw_mac").focus();},2000);
+            setTimeout(function(){ $('#sccp_hw_mac').focus();},2000);
+        } else {
+            $('#ajaxsubmit2').removeAttr('disabled');
+            $('#ajaxsubmit').removeAttr('disabled');
         };
       });
 
diff --git a/conf/sccpgeneral.xml.v433 b/conf/sccpgeneral.xml.v433
index 48e3d92..47522ad 100644
--- a/conf/sccpgeneral.xml.v433
+++ b/conf/sccpgeneral.xml.v433
@@ -1253,8 +1253,9 @@ and open the template in the editor. Base Version before all crash :-)
             <label>Device SEP ID.[XXXXXXXXXXXX]=MAC</label>
             <input>
                 <name>mac</name>
-                <default>000000000</default>
+                <default></default>
                 <class>sccp-custom</class>
+                <options></options>
             </input>
             <help>The MAC address of the phone. You must specify 12 characters in the format XXXX.XXXX.XXXX or XX-XX-XX-XX-XX-XX or XXXXXXXXXXXX</help>
         </item>
@@ -1282,7 +1283,7 @@ and open the template in the editor. Base Version before all crash :-)
             <label>Device SEP ID</label>
             <input>
                 <name>mac</name>
-                <default>000000000</default>
+                <default></default>
                 <class>sccp-custom</class>
                 <options readonly="readonly"></options>
             </input>