That is due to missing package indicator-sound.
Latest version from PPA will quit showing an error dialog instead of
crashing straightaway.
Most parts of the application disable themselves if they can not find
the required schema and allow the rest to start up, but there are some
problematic ones
Public bug reported:
It doesn't start and this message appeares in konsole:
File
"/usr/lib/python3/dist-packages/UnityTweakTool/section/sphagetti/unity.py",
line 93, in refresh
interested_players = gsettings.sound.get_strv('interested-media-players')
AttributeError: 'NoneType' object has no
