[kennu]

My impression is that the current Sonos app becomes unusable when your home Internet connection is unstable. It usually works fine here, but when our 5G starts switching channels due to a snowstorm, the Sonos app becomes erratic.

I understand there's also issues with mDNS discovery and maybe other things, but the worst mistake seems to be the assumption that everybody has a stable Internet connection all the time.

There are other apps that have made a similar mistake. E.g. Ubiquiti's UniFi management app has problems connecting to the local LAN console if you originally signed in using a cloud account and Internet becomes unstable.

One app that handles this right is the Home Assistant Companion app. It detects when you're using a local WiFi SSID and connects directly to the internal LAN address which always works, and otherwise uses the cloud connection or public WAN address.