Been happening to me a bit quite recently too.
Also had it disconnect from the wiim a couple of times just from skipping to the next track.
Who to blame...?
No such issue here - I can fire up Tidal on multiple devices and tidal connect all of them to the same wiim and see / control volume, playback etc. from any of them.
As for spotify hi res, I'll only believe it when I see it!
The rest of the family use spotify exclusively, but I doubt they'll even notice if/when it arrives.
I'm sure I will though, as I pay the bill...