Hey @antonm123, welcome to the Community.
Hope you are doing great!
Crossfade is not an issue of Spotify but a feature implemented into the app.
To enjoy a flawless stream of songs just go to Your Library inside Settings, the gear icon top right corner, and find Playback section. You should enable Gapless Playback which should be located right below the Crossfade slider 🙂
You should be good to go now 🙂
Here is a FAQ for this feature and you can find my tip there as well.
Have a nice day!
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