You are using staging server - a separate instance of the ESP Component Registry that allows you to try distribution tools and processes without affecting the real registry.
# ESP-GMF-Audio - [![Component Registry](https://components.espressif.com/components/espressif/esp_gmf_audio/badge.svg)](https://components.espressif.com/components/espressif/esp_gmf_audio)
idf.py add-dependency "jason-mao/gmf_audio^0.0.2"