[solved]PaperUI not showing channels from discovered things

I’m have sonos devices which are correctly discovered by the PaperUI. I added them to the Things using a custom name. When selecting one of them under “Configurations/Things” the device is displayed with the status “Online” displayed as well as the label “Channels”. Most of the time no more information is displayed. Only in some some rare cases a list of those channels is displayed (like "Control, CurrentArtist…). Shouldn’t those channels be displayed all the time?
OS Win10 Browser Firefox 45.0.1

After adding the FritzBox-binding, all the Sonos-Players do show the complete Channel list.
For me the Problem is solved, can’t tell if the observed Problem was only for me.