Streamers will normally play m3u playlists from AssetUPnP R7.4 etc. of music files referenced on a “NAS”.
Playlists of external URLs using http and https URLs are also a valid m3u format and widely used.
These play on other systems such as Denon and Linn (including mp3, aac, flac and flac hi-res formats) but not on a Naim MuSo Gen 1.
They actually play for about two seconds on the MuSo then stop. This would appear to be a bug.
I have not able to test them on other Naim streamers.
An example m3u file of external radio stations using both http and https URLs and the various formats is:-
#PLAYLIST:Internet Radio: JAZZ Music
#EXTINF:0,The Jazz Groove Mix #1 (San Francisco, USA)
#EXTINF:0,Jazz 24/7 (WGBH) (Boston, USA)
#EXTINF:0,Naim Jazz (UK) (flac)
#EXTINF:0,SuperStereo 7 Jazz (Chile) (flac hi-res)
#EXTINF:0,Jazzed Radio (UK)