Thanks for the details guys. We've been looking into iOS battery usage and so far it's all seemed pretty normal. The biggest drain on the battery that Sonos uses comes in two pieces, first off, the app is still going to try and keep alive access to your players while you're on a wireless network, which, even in background mode, will use a bit of the battery. The second piece, is that when you're using the iOS Lock Screen controls on Sonos, the app is "playing" a silent track on the phone. This is the only way to have a non-media app take control over the lock screen in iOS.
If you think your system is seeing an unusually high amount of battery usage, we're happy to take a look, and I'd encourage you to
give us a call on our support line.
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