[gorschten]

Alsa was the solution. :-)

But after a while (seconds to minutes) the sound stoped sometimes. Setting the first "Audio Ausgabegerät" to "default" fixed it. The other settings are ok. So now it works! :-D
Thank you all!!!

[fritsch]

looks good, yes. If you want TrueHD and Flac 5.1 also as AC3 5.1 you can additionally enable the Dolby Transcode Option.

[gorschten]

where can I enable it?

[fritsch]

You posted the screenshots :-) It's on pic03 "-Dolby Digital Umwandlung einschalten"