You can listen to podcasts at various speeds in Spotify (0.5x, 0.8x, etc), but there is no method for this in the API for the web player. I am building a (non commercial) website to help people learn piano songs by ear (here's the site, it's a work in progress ), and it would be very helpful to be able to play songs at different speeds. Is this likely to be implemented?
Right now, there's no way to change the speed of songs through the Web Playback SDK, but if this is something you'd like to see, I recommend creating a new idea on the Ideas board. That way, Spotify can keep track of it. Feel free to give me a shout, if you have any questions!
Have a good one,
HuboRock Star 16
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