Spotify forces you into this. I have a playlist with a little over 2 thousand songs, and every time I start the playlist it plays the same hundred or so songs because of their shuffle algorithm.
You can use sites like these to randomize your playlist. You can have it randomize the playlist or create a randomized copy if you want to keep the original.
I usually start the playlist, turn on their crappy shuffle to get me to a random position in the randomized playlist, then disable their profitability maximizer shuffle.
It doesn't seem to matter where i play music.
I feel like the same pattern happens everywhere.
Like, there is a set if songs no matter how big the list is, it always seems to play way more often than others.
This doesn't happen to me all the time, or even most of the time, but when it does oh my God is it irritating. It's gotta be some bug with loading more content, or a connection issue. Because I could still play those 5 songs while completely disconnected from the Internet, which means they're already downloaded to the device in some capacity. It's just not loading more from the web.