Here are details of the system I am using with the TDAI 3400. Excuse lack of technical expertise.
TDAI is said to be always Roon ready. (I have tried switching it to Roon Ready on the display and this has made no difference.) TDAI connected by cable to BT Smart Hub.
The Roon app is on my iPad. It opens with Choose your Roon Core. This does not detect device so the Roon symbol continues to pulsate and nothing happens. I have tried entering the IP of the TDAI 3400 manually and that does not work. iPad is running OS14.1. Connected via wireless.
LAN is a BT Smart Hub. I am afraid I don’t know the specific details. We will have used the default settings. It is plugged into a BT landline. We have one BT mini Whole Home wi-fi disc at the top of the house to improve the coverage.
I am attempting to stream music from Qobuz using a mconnectHD app (Qobuz not yet native on Lyngdorf). The Qobuz app is on my iPad and iPhone. mconnectHD is on my iPad.