So get connected to my Pioneer receiver.
WLAN configuration was done quickly and easily.
The first system update was promptly available and was a few minutes later
wait successfully installed.
The first test with "Tron Legacy" was the Oberhammer.
The sound crystal clear, the picture razor sharp.
But since I only a FullHD 40 "TV call my own at the moment I have all 4K options disabled.
So I can not make any statements about 4K at the moment.
The playback of median on my DLNA server XBMC from MKV and AVI and WMV files normal was flawless, the sound is played back properly on the Pioneer receiver or via pass-through from the TV.