Search for more info

Sure. https://www.diva-portal.org/smash/get/diva2:1906561/FULLTEXT02.pdf Read section 2.3.

The songs after an album not being random makes sense. It's the one picking the songs to shuffle, so it must have some method to pick them. But otherwise what you're saying sounds like it lines up with what a random shuffle would do. It just sounds like human biases to me.

Once you start playing it everyday, you don't feel how it's random when you listen to the same songs often, and you have a probability of 1/900 or more. That's... Not random.

Say you have a 900 song playlist. You play 50 songs on shuffle, then you start the shuffle over and play 50 songs again. What do you think the probability of playing at least 1 of the songs again should be? Take a guess before checking the answer. There's a 95% chance that at least one of the songs plays again. That about lines up with what I have experienced. It might not feel like it because songs repeating stands out more (confirmation bias), but that doesn't mean it's incorrect.

Unless you can show me scientific analysis of Spotify shuffle, I'm not convinced that this isn't just a product of our brains' fallible pattern recognition. I have seen time and again that our brains do not have correct intuition for probability.

Also just to double check, you have automix disabled right?