Well, for tvheadend you need to install tvheadend htsp client not iptv simple.
Thanks for your answer! I deinstalled iptv simple and installed Tvheadend htsp client.
At least I receive a system sound. But there are still no channels.
Is there a debug option, in order to test, wether the Cine s2 is recognized by Tvheadend?
Do I have to initiate the channel scan?