I am aware this feature request has been raised many times in the past, but the threads I found are now closed to further comments, so I am posting a new one here.
I recently bought a Sonos Era 100 and I have been loving it so far. One enhancement I would really love to see, though, is more consistent loudness between tracks when listening to Spotify (especially playlists and shuffle).
For reference, I also use a WiiM Pro streamer to listen to Spotify. WiiM added a toggle to enable/disable Spotify volume normalization in 2025 (*1), and it significantly improved the listening experience. As much as I love my Sonos, WiiM remains my go-to streamer when I need consistent loudness and don't want to keep manually adjusting the volume for each track that’s too quiet or too loud. I would love Sonos to offer feature parity here so the Sonos experience remains fully competitive.
What I am requesting:
Please provide a user-facing option for volume normalization when using Spotify Connect on Sonos (or clearly document whether/how Sonos currently applies normalization for Spotify Connect).
Why I believe this is feasible:
I asked claude.ai about how WiiM might have implemented Spotify normalization, and the explanation was that WiiM could be using Spotify Commercial Hardware integration (Spotify eSDK), where the device can receive per-track normalization gain metadata and apply it on-device during playback. Spotify eSDK changelogs mention the addition of loudness normalization support in Version 3.199.303 (*2), and the Spotify eSDK API reference documents the SpStreamInfo.gain_mdb field, defined as "audio normalization gain (in mdB) to apply to the stream" (*3).
Based on this, it seems plausible that Sonos could implement (or expose) loudness normalization for Spotify Connect in a similar way, i.e. by applying service-provided, ReplayGain-style gain metadata at playback time, avoiding any need for Sonos to analyze the loudness of the live audio stream.
If enabling or exposing this requires coordination with Spotify, I hope Sonos can work with them to support it.
Thank you!
References:
*1: https://forum.wiimhome.com/threads/wiim-pro-firmware-v4-8-712747-update-apr-3-2025.6881/
*2: https://developer.spotify.com/documentation/commercial-hardware/implementation/changelog
*3: https://developer.spotify.com/documentation/commercial-hardware/implementation/reference/latest
P.S. I’ve seen mixed messaging in the Sonos Community from Sonos Staff, and this is one reason I’m asking for a clear documentation:
