kdialog: sound file from notifyrc file was not found,

[René J.V. Bertin]

I can't check right now, but I recall seeing this kind of message when I first started installing KF5 applications before I installed the Plasma5 component that provides things required not provided by KNotifications. A bit curious if you ask me, given how KNotifications is supposed to be cross-platform and Plasma5 is jealously defended as not to be used outside of Plasma5 desktop environments.
(In the end I patch KNotifications in my packaging so it calls Qt's equivalent of the sysbeep when a notification requires sound and has no existing sound file to be played.)

R.