Hi Seb, thanks, but already did that. I have a local Unbound DNS server running which forwards (without caching) the DTAG domains directly to the DTAG DNS server and all others to the router. But didn't help... Best Regards, Klaus -----Ursprüngliche Nachricht----- Von: Sebastian Kemper <sebastian_ml@gmx.net> Gesendet: Dienstag, 27. November 2018 19:09 An: FreeSWITCH Users Help <freeswitch-users@lists.freeswitch.org>; ITutu - Mailings <mailings@itutu.de> Betreff: Re: [Freeswitch-users] Problem with German Telekom SIP Trunk Hi Klaus, I had some DNS issue with DTAG years ago, admittedly on a subscriber SIP line, until somebody suggested to use the DTAG nameserver instead of the third party nameserver I was using back then. Problem solved. Maybe the fix for you is the same. Regards, Seb