Guessing most likely this is a duplicate of: https://bugs.launchpad.net/ubuntu/+source/qtubuntu-media/+bug/1506953
Where the media-hub probably crashed and things are not recovering properly under the covers which causes the ringing to stop.
Guessing most likely this is a duplicate of: /bugs.launchpad .net/ubuntu/ +source/ qtubuntu- media/+ bug/1506953
https:/
Where the media-hub probably crashed and things are not recovering properly under the covers which causes the ringing to stop.