After initial logon problems it worked as I have encryption turned off in the FB.
Then tested and, of course, stupid because a) no security, b) no HD telephony and c) no Web radio goes.
After about 30 minutes logged the repeater of the FB (DECT button 6 seconds), then the FB switched back to encryption, rebooted once and repeated logon process. And lo and behold: a) Encrypted connection goes, b) HD telephony possible and c) the radio repeaters goes.
I think this is at some point a new firmware draufgekommen, unfortunately we see this in the FB nothing. Interestingly, the repeater 1 is that under the FB menu DECT-Monitor then emerged is.
I've now just ordered the 2nd repeater. Let's see if the back has 2 months to deliver.
So with a little patience and try to work everything. At least for me :-)