diff --git a/scripts/pi-hole/js/groups-clients.js b/scripts/pi-hole/js/groups-clients.js
index 919eb5aa..74614de9 100644
--- a/scripts/pi-hole/js/groups-clients.js
+++ b/scripts/pi-hole/js/groups-clients.js
@@ -32,12 +32,12 @@ function reload_client_suggestions() {
           continue;
         }
 
-        // Add MAC address
-        var text = key.toUpperCase();
-
-        // Check if this is a valid MAC address (skip mock devices)
-        if (!utils.validateMAC(text)) {
-          continue;
+        var text = key,
+          key_plain = key;
+        if (key.startsWith("IP-")) {
+          // Mock MAC address for address-only devices
+          key_plain = key.substring(3);
+          text = key_plain;
         }
 
         // Append host name if available
@@ -45,7 +45,7 @@ function reload_client_suggestions() {
           text += " (" + data[key] + ")";
         }
 
-        sel.append($("<option />").val(key).text(text));
+        sel.append($("<option />").val(key_plain).text(text));
       }
     },
     "json"
diff --git a/scripts/pi-hole/php/groups.php b/scripts/pi-hole/php/groups.php
index 275aee6e..3e818b0c 100644
--- a/scripts/pi-hole/php/groups.php
+++ b/scripts/pi-hole/php/groups.php
@@ -216,7 +216,7 @@ if ($_POST['action'] == 'get_groups') {
         // Loop over results
         $ips = array();
         while ($res = $query->fetchArray(SQLITE3_ASSOC)) {
-            $ips[$res['hwaddr']] = $res['name'] !== null ? $res['name'] : '';
+            $ips[strtoupper($res['hwaddr'])] = $res['name'] !== null ? $res['name'] : '';
         }
         $FTLdb->close();
 
@@ -227,8 +227,11 @@ if ($_POST['action'] == 'get_groups') {
 
         // Loop over results, remove already configured clients
         while (($res = $query->fetchArray(SQLITE3_ASSOC)) !== false) {
-            if (isset($ips[$res['hwaddr']])) {
-                unset($ips[$res['hwaddr']]);
+            if (isset($ips[$res['ip']])) {
+                unset($ips[$res['ip']]);
+            }
+            if (isset($ips["IP-".$res['ip']])) {
+                unset($ips["IP-".$res['ip']]);
             }
         }