Your ROOT_URL in app.ini is https://source.parasitstudio.de:63000/ but you are visiting https://source.parasitstudio.de/wirtz/OpenAudio_ArduinoLibrary/src/commit/a27123ec6464081efaa932f8b85956285a6217d2/examples/testCompressor2 You should set ROOT_URL correctly, otherwise the web may not work correctly.