Alter behavior of the zero button in PiP mode. The exact behavior may be

Alter behavior of the zero button in PiP mode. The exact behavior may be
configured by changing the value of the 'Behaviour of 0 key in PiP-mode'
property  in the settings menu. Possible values are:

- standard
  the behavior of the zero button is remains as is (switch to last channel)
- swap
  the zero button swaps the pip service with the active
- swap and stop
  the zero button swaps the pip service with the active and then turns
  pip off
- stop
  turns pip off

Patch by John Holland <johnbock@i-have-a-dreambox.com>, with some
modifications.