diff --git a/.env.development b/.env.development
index 7b36366..419aa53 100644
--- a/.env.development
+++ b/.env.development
@@ -6,6 +6,6 @@ NEXT_PUBLIC_USE_MOCK_BACKEND_LOOP_START=false
 NEXT_PUBLIC_EXPORT_STATIC=false
 NEXT_PUBLIC_USE_CGI=false
 # App-Versionsnummer
-NEXT_PUBLIC_APP_VERSION=1.6.520
+NEXT_PUBLIC_APP_VERSION=1.6.521
 NEXT_PUBLIC_CPL_MODE=json   # json (Entwicklungsumgebung) oder jsSimulatedProd (CPL ->CGI-Interface-Simulator) oder production (CPL-> CGI-Interface Platzhalter)
 
diff --git a/.env.production b/.env.production
index 8687609..30474a1 100644
--- a/.env.production
+++ b/.env.production
@@ -5,5 +5,5 @@ NEXT_PUBLIC_CPL_API_PATH=/CPL
 NEXT_PUBLIC_EXPORT_STATIC=true
 NEXT_PUBLIC_USE_CGI=true
 # App-Versionsnummer
-NEXT_PUBLIC_APP_VERSION=1.6.520
+NEXT_PUBLIC_APP_VERSION=1.6.521
 NEXT_PUBLIC_CPL_MODE=production
\ No newline at end of file
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1038146..8593648 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,13 @@
+## [1.6.521] – 2025-07-02
+
+- refactor: Admin-Status direkt aus Redux ausgelesen und Props entfernt
+
+- isAdminLoggedIn wird jetzt direkt aus authSlice im Redux-Store gelesen
+- useAdminAuth und Prop-Weitergabe entfernt
+- Flackern des Firmware-Buttons dauerhaft behoben
+- Codestruktur vereinfacht und stabilisiert
+
+---
 ## [1.6.520] – 2025-07-02
 
 - refactor: Admin-Status direkt aus Redux ausgelesen und Props entfernt
diff --git a/package-lock.json b/package-lock.json
index f2ac301..05390eb 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "cpl-v4",
-  "version": "1.6.520",
+  "version": "1.6.521",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "cpl-v4",
-      "version": "1.6.520",
+      "version": "1.6.521",
       "dependencies": {
         "@fontsource/roboto": "^5.1.0",
         "@iconify-icons/ri": "^1.2.10",
diff --git a/package.json b/package.json
index 0bbd620..3f7533e 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "cpl-v4",
-  "version": "1.6.520",
+  "version": "1.6.521",
   "private": true,
   "scripts": {
     "dev": "next dev",
diff --git a/pages/_app.tsx b/pages/_app.tsx
index 675abcf..1b794df 100644
--- a/pages/_app.tsx
+++ b/pages/_app.tsx
@@ -23,6 +23,7 @@ import { getReferenceCurveBySlotThunk } from "@/redux/thunks/getReferenceCurveBy
 import { getAllTDRReferenceChartThunk } from "@/redux/thunks/getAllTDRReferenceChartThunk";
 import { getTDRChartDataByIdThunk } from "@/redux/thunks/getTDRChartDataByIdThunk";
 import { getLoopChartDataThunk } from "@/redux/thunks/getLoopChartDataThunk";
+import { getAuthThunks } from "@/redux/thunks/getAuthThunks";
 import Modal from "react-modal";
 if (typeof window !== "undefined") {
   Modal.setAppElement("#__next"); // oder "#root", je nach App-Struktur
@@ -54,6 +55,7 @@ function AppContent({
     const pathname = window.location.pathname;
 
     const loadAndDispatch = () => {
+      dispatch(getAuthThunks());
       if (pathname.includes("kabelueberwachung")) {
         dispatch(getKueDataThunk());
       } else if (pathname.includes("digitalOutputs")) {
diff --git a/redux/thunks/getAuthThunks.ts b/redux/thunks/getAuthThunks.ts
new file mode 100644
index 0000000..c25415b
--- /dev/null
+++ b/redux/thunks/getAuthThunks.ts
@@ -0,0 +1,12 @@
+// redux/thunks/getAuthThunks.ts
+import { createAsyncThunk } from "@reduxjs/toolkit";
+import { fetchAuthService } from "@/services/fetchAuthService";
+import { setAdminLoggedIn } from "@/redux/slices/authSlice";
+
+export const getAuthThunks = createAsyncThunk(
+  "auth/getAuthThunks",
+  async (_, { dispatch }) => {
+    const { isAdminLoggedIn } = fetchAuthService();
+    dispatch(setAdminLoggedIn(isAdminLoggedIn)); // boolean, nicht string!
+  }
+);
diff --git a/services/fetchAuthService.ts b/services/fetchAuthService.ts
new file mode 100644
index 0000000..0a835a2
--- /dev/null
+++ b/services/fetchAuthService.ts
@@ -0,0 +1,6 @@
+// services/fetchAuthService.ts
+export const fetchAuthService = () => {
+  const isAdminLoggedInRaw = localStorage.getItem("isAdminLoggedIn");
+  const isAdminLoggedIn = isAdminLoggedInRaw === "true"; // <– explizit Boolean
+  return { isAdminLoggedIn };
+};