PC Windows: https://www.microsoft.com/en-us/p/upnp-analyser/9nblggh69pdn?activetab=pivot:overviewtab
Android Phone
upnp Discovery was the app in previous post.
Spotify Discover use https://play.google.com/store/apps/details?id=com.druk.servicebrowser&hl=en_GB&gl=US
These tools will establish of you S1o is discoverable on your LAN.
Kevin