AirPlay is working well from a Mac running Mojave. A couple of questions:
1. After I switch the Soundtouch locally (i.e, on the device) to one of the six radio stations, how do I subsequently switch back to the AirPlay feed, locally? Right now, I have to go back to the AirPlay source Mac, and in Apple Music/iTunes, disconnect the Soundtouch and reconnect it again.
2. Related: when I go back to the Mac, iTunes/Apple Music still displays the SoundTouch as an active destination, although at that time the SoundTouch is currently playing an internet radio station. Is that correct, or am I missing something?
Also, possibly related: none of the internet radio stations were working this morning, but it all seems to be working again now. Did Houston have a problem, perchance? 😉
Regarding your internet radio stations, TuneIn had a short outage and all there services should be back up and running, let us know if you are still having issues.
You will not be able to switch to Airplay 2 locally on the device, you will need to switch to this through your source device. It is normal for the SoundTouch to be an active device even if it is playing another source.
I hope this helps. If there is anything else I can do, please reach out again!