Kubuntu 14.10: Muon update manager no longer appearing in tray

[Annorax]

I'm running Kubuntu 14.10 and one day I noticed that I haven't gotten any updates for a while (no tray icon appearing) so I ran sudo apt-get update && sudo apt-get upgrade and installed some updates just fine.

Then a few days later I noticed the same thing, no updates in the tray so this time I ran the GUI Muon Update Manager and it found updates so I installed them.

I haven't changed anything - one day the updater icon stopped appearing in my KDE system tray. Other icons are still there. Any ideas what might be wrong?

[Snowhog]

Launch Muon Package Manager and check Settings > Configure Software Sources and check the Updates tab.