diff --git a/.github/workflows/ctest.yml b/.github/workflows/ctest.yml
index da07df8d..01d342a0 100644
--- a/.github/workflows/ctest.yml
+++ b/.github/workflows/ctest.yml
@@ -13,11 +13,17 @@ jobs:
     steps:
       - uses: actions/checkout@v3
 
+      - name: Set up Python 3.9
+        uses: actions/setup-python@v4
+        with:
+          python-version: 3.9
+
+
       - name: Install packages
         shell: bash
         run: |
           sudo apt-get update
-          sudo apt-get install octave octave-common octave-signal sox python3 python3-pip portaudio19-dev python3-pyaudio
+          sudo apt-get install octave octave-common octave-signal sox portaudio19-dev python3-pyaudio
           pip3 install psutil crcengine ujson pyserial numpy structlog sounddevice
           pip3 install pytest pytest-rerunfailures