diff --git a/.github/workflows/docker_debian_unified.yml b/.github/workflows/docker_debian_unified.yml
index 034f7a1ba..a058949b7 100644
--- a/.github/workflows/docker_debian_unified.yml
+++ b/.github/workflows/docker_debian_unified.yml
@@ -21,6 +21,10 @@ on:
 env:
   DOCKER_IMAGE_NAME: rpi-jukebox-rfid
   CACHE_SCOPE: ${{ github.ref }}-debian-unified
+  LOCAL_REGISTRY_PORT: 5005
+  MATRIX_DEBIAN_VERSION_NAME: "['bullseye', 'buster']"
+  MATRIX_USERNAME: "['pi', 'hans']"
+  MATRIX_TEST_SCRIPT: "['run_installation_tests.sh', 'run_installation_tests2.sh', 'run_installation_tests3.sh']"
 
 jobs:
   prepare:
@@ -28,16 +32,18 @@ jobs:
 
     outputs:
       runs_on: ubuntu-latest
+      platform: linux/arm/v7
 
-      # Definition of the matrix values for the subsequent jobs
-      matrix_debian_version: "['bullseye', 'buster']"
-      matrix_username: "['hans']" #"['pi', 'hans']"
-      matrix_test_script: "['run_installation_tests.sh', 'run_installation_tests2.sh', 'run_installation_tests3.sh']"
+      matrix_debian_version_name: ${{ env.MATRIX_DEBIAN_VERSION_NAME }}
+      matrix_username: ${{ env.MATRIX_USERNAME }}
+      matrix_test_script: ${{ env.MATRIX_TEST_SCRIPT }}
 
-      cache_scope: ${{ steps.set-cache_scope.outputs.cache_scope }}
       image_tag_name: ${{ steps.set-image_tag_name.outputs.image_tag_name }}
+      image_tag_name_local_base: ${{ steps.set-image_tag_name_local_base.outputs.image_tag_name_local_base }}
       image_file_path: ${{ steps.set-image_file_path.outputs.image_file_path }}
+      cache_scope: ${{ steps.set-cache_scope.outputs.cache_scope }}
       cache_key: ${{ steps.set-cache_key.outputs.cache_key }}
+      local_registry_port: ${{ steps.set-local_registry_port.outputs.local_registry_port }}
 
     steps:
       - name: Set Output cache_scope
@@ -56,6 +62,13 @@ jobs:
         id: set-cache_key
         run: echo "cache_key=${{ steps.set-cache_scope.outputs.cache_scope }}-${{ github.sha }}#${{ github.run_attempt }}" >> $GITHUB_OUTPUT
 
+      - name: Set Output local_registry_port
+        id: set-local_registry_port
+        run: echo "local_registry_port=${{ env.LOCAL_REGISTRY_PORT }}" >> $GITHUB_OUTPUT
+
+      - name: Set Output image_tag_name_local_base
+        id: set-image_tag_name_local_base
+        run: echo "image_tag_name_local_base=localhost:${{ steps.set-local_registry_port.outputs.local_registry_port }}/${{ steps.set-image_tag_name.outputs.image_tag_name }}-base" >> $GITHUB_OUTPUT
 
   build:
     needs: [prepare]
@@ -64,12 +77,12 @@ jobs:
         registry:
           image: registry:2
           ports:
-            - 5000:5000
+            - ${{ needs.prepare.outputs.local_registry_port }}:5000
 
     strategy:
         fail-fast: false
         matrix:
-          debian_version: ${{ fromJSON(needs.prepare.outputs.matrix_debian_version) }}
+          debian_version_name: ${{ fromJSON(needs.prepare.outputs.matrix_debian_version_name) }}
 
     steps:
     - uses: actions/checkout@v4
@@ -91,12 +104,12 @@ jobs:
         push: true
         file: ./ci/Dockerfile.debian.test_install_unified.armv7
         target: test
-        platforms: linux/arm/v7
-        tags: localhost:5000/${{ format( needs.prepare.outputs.image_tag_name, matrix.debian_version) }}-base
-        cache-from: type=gha,scope=${{ format( needs.prepare.outputs.cache_scope, matrix.debian_version) }}
-        cache-to: type=gha,mode=max,scope=${{ format( needs.prepare.outputs.cache_scope, matrix.debian_version) }}
+        platforms: ${{ needs.prepare.outputs.platform }}
+        tags: ${{ format( needs.prepare.outputs.image_tag_name_local_base, matrix.debian_version_name) }}
+        cache-from: type=gha,scope=${{ format( needs.prepare.outputs.cache_scope, matrix.debian_version_name) }}
+        cache-to: type=gha,mode=max,scope=${{ format( needs.prepare.outputs.cache_scope, matrix.debian_version_name) }}
         build-args: |
-          DEBIAN_VERSION=${{ matrix.debian_version }}
+          DEBIAN_VERSION_NAME=${{ matrix.debian_version_name }}
           GIT_BRANCH=${{ github.ref_name }}
           GIT_URL=${{ github.server_url }}/${{ github.repository }}
 
@@ -109,13 +122,13 @@ jobs:
         push: false
         file: ./ci/Dockerfile.debian.test_install_unified.armv7
         target: test-update
-        platforms: linux/arm/v7
-        tags: ${{ format( needs.prepare.outputs.image_tag_name, matrix.debian_version) }}
-        cache-from: type=gha,scope=${{ format( needs.prepare.outputs.cache_scope, matrix.debian_version) }}
-        # DON'T use 'cache-to' here as then the layer is cached and this build would be useless
-        outputs: type=docker,dest=${{ format( needs.prepare.outputs.image_file_path, matrix.debian_version) }}
+        platforms: ${{ needs.prepare.outputs.platform }}
+        tags: ${{ format( needs.prepare.outputs.image_tag_name, matrix.debian_version_name) }}
+        cache-from: type=gha,scope=${{ format( needs.prepare.outputs.cache_scope, matrix.debian_version_name) }}
+        # DON'T use 'cache-to' here as the layer is then cached and this build would be useless
+        outputs: type=docker,dest=${{ format( needs.prepare.outputs.image_file_path, matrix.debian_version_name) }}
         build-args: |
-          BASE_TEST_IMAGE=localhost:5000/${{ format( needs.prepare.outputs.image_tag_name, matrix.debian_version) }}-base
+          BASE_TEST_IMAGE=${{ format( needs.prepare.outputs.image_tag_name_local_base, matrix.debian_version_name) }}
 
 
     - name: Cache Check Docker Image
@@ -123,15 +136,15 @@ jobs:
       id: cache-restore
       with:
         lookup-only: true
-        key: ${{ format( needs.prepare.outputs.cache_key, matrix.debian_version) }}
-        path: ${{ format( needs.prepare.outputs.image_file_path, matrix.debian_version) }}
+        key: ${{ format( needs.prepare.outputs.cache_key, matrix.debian_version_name) }}
+        path: ${{ format( needs.prepare.outputs.image_file_path, matrix.debian_version_name) }}
 
     - name: Cache Save Docker Image
       uses: actions/cache/save@v3
       if: ${{ ! steps.cache-restore.outputs.cache-hit }}
       with:
         key: ${{ steps.cache-restore.outputs.cache-primary-key }}
-        path: ${{ format( needs.prepare.outputs.image_file_path, matrix.debian_version) }}
+        path: ${{ format( needs.prepare.outputs.image_file_path, matrix.debian_version_name) }}
 
 
   test:
@@ -141,7 +154,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        debian_version: ${{ fromJSON(needs.prepare.outputs.matrix_debian_version) }}
+        debian_version_name: ${{ fromJSON(needs.prepare.outputs.matrix_debian_version_name) }}
         username: ${{ fromJSON(needs.prepare.outputs.matrix_username) }}
         test_script: ${{ fromJSON(needs.prepare.outputs.matrix_test_script) }}
 
@@ -155,19 +168,19 @@ jobs:
     - name: Cache Restore Docker Image
       uses: actions/cache/restore@v3
       with:
-        key: ${{ format( needs.prepare.outputs.cache_key, matrix.debian_version) }}
-        path: ${{ format( needs.prepare.outputs.image_file_path, matrix.debian_version) }}
+        key: ${{ format( needs.prepare.outputs.cache_key, matrix.debian_version_name) }}
+        path: ${{ format( needs.prepare.outputs.image_file_path, matrix.debian_version_name) }}
         fail-on-cache-miss: true
 
     - name: Load Docker Image
       run: |
-        docker load --input ${{ format( needs.prepare.outputs.image_file_path, matrix.debian_version) }}
+        docker load --input ${{ format( needs.prepare.outputs.image_file_path, matrix.debian_version_name) }}
 
-    - name: Run Test ${{ matrix.debian_version }}-${{ matrix.username }}-${{ matrix.test_script }}
+    - name: Run Test ${{ matrix.debian_version_name }}-${{ matrix.username }}-${{ matrix.test_script }}
       uses: tj-actions/docker-run@v2
       with:
-        image: ${{ format( needs.prepare.outputs.image_tag_name, matrix.debian_version) }}
-        options: --platform linux/arm/v7 --user ${{ matrix.username }}
+        image: ${{ format( needs.prepare.outputs.image_tag_name, matrix.debian_version_name) }}
+        options: --platform ${{ needs.prepare.outputs.platform }} --user ${{ matrix.username }}
         name: ${{ matrix.test_script }}
         args: |
           ./${{ matrix.test_script }}
diff --git a/ci/Dockerfile.debian.test_install_unified.armv7 b/ci/Dockerfile.debian.test_install_unified.armv7
index 7f9bdddff..4e039e421 100644
--- a/ci/Dockerfile.debian.test_install_unified.armv7
+++ b/ci/Dockerfile.debian.test_install_unified.armv7
@@ -1,8 +1,8 @@
 # Target to build and install all needed base configuration and packages
-ARG DEBIAN_VERSION=bullseye
+ARG DEBIAN_VERSION_NAME=bullseye
 ARG BASE_TEST_IMAGE=test
-FROM debian:${DEBIAN_VERSION}-slim as base
-ARG DEBIAN_VERSION
+FROM debian:${DEBIAN_VERSION_NAME}-slim as base
+ARG DEBIAN_VERSION_NAME
 
 ENV DOCKER_RUNNING=true
 RUN touch /boot/cmdlinetxt
@@ -14,8 +14,8 @@ RUN apt-get update \
     apt-utils \
     curl \
     gnupg \
-  && echo "deb http://raspbian.raspberrypi.org/raspbian/ ${DEBIAN_VERSION} main contrib non-free rpi" > /etc/apt/sources.list.d/raspi.list \
-  && echo "deb http://archive.raspberrypi.org/debian/ ${DEBIAN_VERSION} main" >> /etc/apt/sources.list.d/raspi.list \
+  && echo "deb http://raspbian.raspberrypi.org/raspbian/ ${DEBIAN_VERSION_NAME} main contrib non-free rpi" > /etc/apt/sources.list.d/raspi.list \
+  && echo "deb http://archive.raspberrypi.org/debian/ ${DEBIAN_VERSION_NAME} main" >> /etc/apt/sources.list.d/raspi.list \
   && curl http://raspbian.raspberrypi.org/raspbian.public.key | apt-key add - \
   && curl http://archive.raspberrypi.org/debian/raspberrypi.gpg.key | apt-key add - \
   && apt-get update \