The cross-device volume control was all working fine in previous version of Spotify (3 editions ago) but again we've lost the ability to control volume playback between mobile phones (iOS or Android) when they are connected to Spotify Connect.
it's unexpected behaviour (intensionally disabled) that the volume can't be controlled from a mobile device when the playback is coming from another mobile device.
However, it is possible to control the volume of the desktop app (PC or Mac) from a phone via Connect (iOS/Android can control PC or MAC Spotify.
We use different devices for playback, it's better to bring second mobile phone to a party and connect it to external speakers instead of dragging full laptop. It's possible to play music from first personal phone but how it will be when somebody call you? The music from Spotify will stop to play! Also notifications sounds is present during playback and interrupt music. Different music songs can be louder or quieter, so we have to get stable function to set volume higher or lower.
Nowadays it's very strange that even the option of volume control between two phones is implemented in Spotify code (function worked three editions ago) but somehow it's intensionally disabled. The question is WHY ? Who not need it not even notice the lack of feature, but we need it for sure.
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