The Volumio Android app (which I bought) hangs after some time of inactivity. For example: if I listen to an entire cd then afterwards the app gives me a message that the webpage (?) cannot be displayed. The only way to resolve this problem is to "kill" the app in system-settings of Android
I had this problem on my previous phone (Android 8) and on my new phone with Android 9. Reinstalling does not help.