I noticed when using the Logitech Media Server emulation mode in Roon with my Squeezebox Radio, that it is not possible to transition to the Now Playing screen when playing radio stations, e.g. with the Radio on the home screen/menu, start playing a live radio station in Roon; choosing the Now Playing menu option results in the “sorry, Dave” ‘bump’ and the display remains on the home menu.
If you’re already on Now Playing when you start a radio station (e.g. because you were playing a song beforehand), then it displays the radio station information (logo, name) fine, but if you browse away from Now Playing (e.g. press home or back), then you can’t get back there.
After some poking around, I discovered that this seems to be because Roon is sending some invalid information for the track info when playing live radio, specifically ‘artist’ and ‘album’ — the title track info contains the radio station name, but the artist and album contain a Lua userdata element (which I don’t know what it is meant to be). hacking the NowPlayingApplet.lua file on the radio to substitute a blank string in this situation (see, e.g. example patch from an extension I wrote, also referenced in this thread) fixes it, and you can browse to Now Playing with radio stations just fine.
Is this something that could be fixed in the Roon LMS implementation? Are there any plans for this, e.g. it would be great if it could be spun out to an extension or something, where the code for this could be shared. At the moment, it is proprietary and we’re unable to see exactly which bits of the LMS API Roon has or hasn’t implemented.