After casting Spotify from my iPhone or Android phone onto my new Chromecast audio device(s) I was disappointed to discover that I could not set the device to extreme quality, even though I am a premium member. It would be good to allow a default extreme quality setting on all devices used on my account or to allow setting the quality in the iOS/Android app.
Support says Spotify transcodes from their native Vorbis codec to 256kbps AAC, which further reduces audio quality, especially since Chromecast Audio seems to natively support Vorbis. Spotify should strive to make their service use the best possible audio quality on any platform, and that doesn't seem to be the case right now with Chromecast.
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