Use the app to FireTV. Installation was straightforward and the contents are with me liquid streamed VDSL 50Mbit). If they are transmitted but the transmission stopped after about 60 minutes and suddenly also read not be restarted. I have even taken the FireTV from power and restart. In the second experiment the same problem with the ZDFmediathek. Other Videos (Amazon Prime, etc.) I could, however so far all problems and without the slightest misfires stream, it is therefore probably not at FireTV.