diff --git a/res/layouts/pages/settings-audio.xml.lua b/res/layouts/pages/settings-audio.xml.lua
index f23426e8..efd925d6 100644
--- a/res/layouts/pages/settings-audio.xml.lua
+++ b/res/layouts/pages/settings-audio.xml.lua
@@ -1,28 +1,27 @@
 function on_open()
-    new_volume_control("audio.volume-master", "master")
-    new_volume_control("audio.volume-regular", "regular")
-    new_volume_control("audio.volume-ui", "ui")
-    new_volume_control("audio.volume-ambient", "ambient")
-    new_volume_control("audio.volume-music", "music")
-
-    gui.reindex("core:pages/settings-audio")
-
-    on_master_change()
-    on_regular_change()
-    on_ui_change()
-    on_ambient_change()
-    on_music_change()
+    new_volume_control("audio.volume-master", "master", "Master Volume")
+    new_volume_control("audio.volume-regular", "regular", "Regular Sounds")
+    new_volume_control("audio.volume-ui", "ui", "UI Sounds")
+    new_volume_control("audio.volume-ambient", "ambient", "Ambient")
+    new_volume_control("audio.volume-music", "music", "Music")
 end
 
-
 function new_volume_control(setting, id, name)
     -- value text label
     document.tracks_panel:add("<label id='l_"..id.."'>-</label>")
     -- value track-bar
     document.tracks_panel:add(string.format(
         "<trackbar id='t_%s' min='0' max='1' value='1' step='0.01' track-width='5' "..
-        " consumer='on_%s_change'/>"
-    , id, id))
+        " consumer='function(x) on_volume_change(%q, %q, %q, x) end'/>"
+    , id, setting, id, name))
+    refresh_label(setting, id, name)
+end
+
+function refresh_label(setting, id, name)
+    document["l_"..id].text = (
+        gui.str(name, "settings")..": "..
+        core.str_setting(setting)
+    )
 end
 
 function on_volume_change(setting, id, name, val)
@@ -31,28 +30,5 @@ function on_volume_change(setting, id, name, val)
     else
         document["t_"..id].value = core.get_setting(setting, val)
     end
-    document["l_"..id].text = (
-        gui.str(name, "settings")..": "..
-        core.str_setting(setting)
-    )
-end
-
-function on_master_change(val)
-    on_volume_change("audio.volume-master", "master", "Master Volume", val)
-end
-
-function on_regular_change(val)
-    on_volume_change("audio.volume-regular", "regular", "Regular Sounds", val)
-end
-
-function on_ui_change(val)
-    on_volume_change("audio.volume-ui", "ui", "UI Sounds", val)
-end
-
-function on_ambient_change(val)
-    on_volume_change("audio.volume-ambient", "ambient", "Ambient", val)
-end
-
-function on_music_change(val)
-    on_volume_change("audio.volume-music", "music", "Music", val)
+    refresh_label(setting, id, name)
 end
diff --git a/src/frontend/UiDocument.cpp b/src/frontend/UiDocument.cpp
index 01d74aff..4ebfcbd2 100644
--- a/src/frontend/UiDocument.cpp
+++ b/src/frontend/UiDocument.cpp
@@ -13,17 +13,21 @@ UiDocument::UiDocument(
     std::shared_ptr<gui::UINode> root,
     std::unique_ptr<scripting::Environment> env
 ) : id(id), script(script), root(root), env(std::move(env)) {
-    buildIndices(map, root);
+    gui::UINode::getIndices(root, map);
 }
 
 void UiDocument::rebuildIndices() {
-    buildIndices(map, root);
+    gui::UINode::getIndices(root, map);
 }
 
 const uinodes_map& UiDocument::getMap() const {
     return map;
 }
 
+uinodes_map& UiDocument::getMapWriteable() {
+    return map;
+}
+
 const std::string& UiDocument::getId() const {
     return id;
 }
@@ -48,19 +52,6 @@ int UiDocument::getEnvironment() const {
     return env->getId();
 }
 
-void UiDocument::buildIndices(uinodes_map& map, std::shared_ptr<gui::UINode> node) {
-    const std::string& id = node->getId();
-    if (!id.empty()) {
-        map[id] = node;
-    }
-    auto container = std::dynamic_pointer_cast<gui::Container>(node);
-    if (container) {
-        for (auto subnode : container->getNodes()) {
-            buildIndices(map, subnode);
-        }
-    }
-}
-
 std::unique_ptr<UiDocument> UiDocument::read(int penv, std::string name, fs::path file) {
     const std::string text = files::read_string(file);
     auto xmldoc = xml::parse(file.u8string(), text);
diff --git a/src/frontend/UiDocument.h b/src/frontend/UiDocument.h
index 1de3c7ac..14cd4f9b 100644
--- a/src/frontend/UiDocument.h
+++ b/src/frontend/UiDocument.h
@@ -42,12 +42,11 @@ public:
 
     const std::string& getId() const;
     const uinodes_map& getMap() const;
+    uinodes_map& getMapWriteable();
     const std::shared_ptr<gui::UINode> getRoot() const;
     const std::shared_ptr<gui::UINode> get(const std::string& id) const;
     const uidocscript& getScript() const;
     int getEnvironment() const;
-    // @brief Collect map of all uinodes having identifiers
-    static void buildIndices(uinodes_map& map, std::shared_ptr<gui::UINode> node);
 
     static std::unique_ptr<UiDocument> read(int env, std::string name, fs::path file);
     static std::shared_ptr<gui::UINode> readElement(fs::path file);
diff --git a/src/graphics/ui/elements/UINode.cpp b/src/graphics/ui/elements/UINode.cpp
index 8bbd0ed3..485b96a9 100644
--- a/src/graphics/ui/elements/UINode.cpp
+++ b/src/graphics/ui/elements/UINode.cpp
@@ -1,5 +1,6 @@
 #include "UINode.h"
 
+#include "containers.h"
 #include "../../core/Batch2D.h"
 
 using gui::UINode;
@@ -256,3 +257,19 @@ void UINode::setGravity(Gravity gravity) {
         reposition();
     }
 }
+
+void UINode::getIndices(
+    std::shared_ptr<UINode> node,
+    std::unordered_map<std::string, std::shared_ptr<UINode>>& map
+) {
+    const std::string& id = node->getId();
+    if (!id.empty()) {
+        map[id] = node;
+    }
+    auto container = std::dynamic_pointer_cast<gui::Container>(node);
+    if (container) {
+        for (auto subnode : container->getNodes()) {
+            getIndices(subnode, map);
+        }
+    }
+}
diff --git a/src/graphics/ui/elements/UINode.h b/src/graphics/ui/elements/UINode.h
index 5f53d0c4..7121c5f2 100644
--- a/src/graphics/ui/elements/UINode.h
+++ b/src/graphics/ui/elements/UINode.h
@@ -6,6 +6,7 @@
 #include <memory>
 #include <string>
 #include <functional>
+#include <unordered_map>
 #include "../../../delegates.h"
 #include "../../../window/input.h"
 
@@ -193,6 +194,12 @@ namespace gui {
         void reposition();
 
         virtual void setGravity(Gravity gravity);
+
+        // @brief collect all nodes having id
+        static void getIndices(
+            std::shared_ptr<UINode> node,
+            std::unordered_map<std::string, std::shared_ptr<UINode>>& map
+        );
     };
 }
 
diff --git a/src/logic/scripting/lua/libgui.cpp b/src/logic/scripting/lua/libgui.cpp
index ece5f19a..53c3efcb 100644
--- a/src/logic/scripting/lua/libgui.cpp
+++ b/src/logic/scripting/lua/libgui.cpp
@@ -219,7 +219,9 @@ static int container_add(lua_State* L) {
     auto node = dynamic_cast<gui::Container*>(docnode.node);
     auto xmlsrc = lua_tostring(L, 2);
     try {
-        node->add(guiutil::create(xmlsrc, docnode.document->getEnvironment()));
+        auto subnode = guiutil::create(xmlsrc, docnode.document->getEnvironment());
+        node->add(subnode);
+        gui::UINode::getIndices(subnode, docnode.document->getMapWriteable());
     } catch (const std::exception& err) {
         luaL_error(L, err.what());
     }