Devialet Chat

Hi 
I have an issue with controlling sound volume via Spotify app when listening to music on my 2 Golds ( linked by dialogue - stereo).
I can fast forward or reverse tracking of any song as it plays via Spotify app on my iPhone X , skip songs ,  but recently if i change volume - it moves volume bar on Spotify , but nothing happens on the golds!
The volume desired on Spotify then quickly reverts to where it originally was .....

So I have to switch to Spark app to modify the volume. Frustrating .

This is new problem , as Spotify would allow me modify volume.

I’ve reinstalled Spotify, rebooted my iPhone , and no better.

Not sure where or his to fix this issue

Any help would be greatly appreciated

Thanks