Comment 10 for bug 850270

First delete .local/share/radiotray simply delete the entire directory.
Then start radiotray in usermode not as root else it will fail again.
Now kill it as it fails also but it writes new files, yes it won't work, I know, just kill it: killall -KILL radiotray (severaltimes)

Change these lines in ./local/share/radiotray/config.xml

  <option name="enable_application_indicator_support" value="false"/>
  <!-- valid options are 'appindicator', 'systray' and 'chooser' -->
  <option name="gui_engine" value="systray"/>

Now start it again, it should work this time.
It's just a matter they alter the install script with these params as default and check the files have the proper owner, as such do not start it with root, it will change the owner.