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/62b89bb14d7c7eb4c9d7860ccd79ad73cf8a78f5/examples/TestFIRGeneralLarge5 You should set ROOT_URL correctly, otherwise the web may not work correctly.