I use my iPhone 6 controlling Spotify on my LG Music Flow speakers. It worked fine for a ling time. Suddenly the icon in the lower right corner has disappeared! It just shows the repeat icon. Where is it? (And yes, I have the latest versions and reinstalled Spotify)
On latest now playing screen it does not show all the time now. It only shows when a connect capable device is available. When available it shows device at very bottom of the screen as does AirPlay when AirPlay devices are available. I use it with ps4 so it shows when my ps4 is on. I'm not familiar with your LG device specifically but just thought I'd share the connect info doesn't show at all times as before. I'm sure you've tried somehow but restart your connect device or activate connect again somehow and look at bottom of now playing screen on iOS device. Hope this helps some.
After latest spotify update 126.96.36.1994 cant see my sony str-dn1050 from spotify connect list. Airplay can see the device and stream music. Testing network and all ok there. Seems to be an issue with this spotify release.
I contacted spotify support, which sayed that sony str dn-1050 is not officially supported and therefore thats all they can say until other information is given. Then i contacted sony support, which answered also. They asked me to check i have spotify premium (i do) and reset the receiver: shut down receiver with main power button, wait few seconds, press the main power button (on front panel) agaen continuously until receiver screen says clearing.. Cleared.
You have to config receiver from scratch (some work depending of setup). But yes indeed spotify from my ipad can see the receiver right away and use spotify connect feature (not airplay). Same thing from my laptop spotify connect works to receiver. If you experience similar issue with similar device.. Maybe try the same. -May the blues be with you.