Hi Stefan,
Thank you for your respone!
Yes, the "rear" speakers turn on, when thay are connected to the front outputs. All speakers are connected directly to the outputs on the TV, so they are not daisy chained (then the surround wouldn't work).
The strange thing is, that after switching cables back and forth suddently the rear speakers worked. It seemed as the rear speaker should be connected before the front ones. I don't understand why, and this is definately not described in the manual. Now I can use speaker mode 1-5.
Now I'm happy to have a working system, but I would of course like to understand why it didn't work in the first place.
Best regards
Jakob