Hi Lintbf
There has been a change either to the Volumio web server or to the libcurl library,
The webserver requires that if a User-Agent is set then it must be non-null in order to access the REST API.
curl -H "" "http://localhost:3000/api/v1/getstate" > getstate1.json
curl -H "User-Agent: myagent" "http://localhost:3000/api/v1/getstate" > getstate2.json
curl -H "User-Agent:" "http://localhost:3000/api/v1/getstate" > volumio.png
If libcurl is used to access the API and a user-agent is not specifically set then it is set to null, and Voliumio returns a PNG rather than JSON, which is why mpd_oled is not seeing the change of state when music is playing.
I’ll update mpd_oled to set a non-null user-agent when accessing the Volumio API
Thank you for reporting the issue!
Adrian.