There has already been a few forum posts about this. But with how the unique way that this company seems to run it's support where you need backup from the rest of the community to have a problem resolved it's gotten no where.
No matter. We shall try again.
Playing a playlist of a decent size (In my tests I've been using a 1000+ song playlist) from for example my PC to my Chromecast it seems to only play perhaps the first 100-120 songs. These songs are truly shuffled. But in this playlist I've added albums from a few artists all in a row, my first two artists on the board being In Flames, then Machinae Supremacy with one Amaranth song in the middle. You can see the layout of the playlist here: spotify:user:zizoor.:playlist:6Sw5k0HiW1P9nONadSUsEt

This means I ONLY hear two different artists at best in a fairly decently sized playlist. This particular issue has persisted for probably over a year and a half and I've completely given up on you fixing it.
The issue can be replicated on any given device too. If i control spotify on my computer via my phone the very same issue happens. You can see this here: 
However if I just shuffle not via Spotify connect it looks like this, and as you can see there are more artists than just machinae supremacy and in flames, its also the same playlist..
The fact that this issue remains and that it's so incredibly easy to test for anyone at spotify is mindboggling. You advertise spotify connect as a key feature to spotify. One of the selling points and yet it's not functional. What are you DOING?
And obviously this post wont reach anywhere because the only way you get recognition here is by getting upvoted like we have some sort of popularity contest. But I plead, FIX IT!
You can replicate this in literally no time. There's no excuse. The other posts I've seen about this problem have both been closed or marked as "Not an issue" and if this isn't an issue then I really don't know what would count, spotify not starting?
Hey folks,
Thanks for sharing all of your feedback. We understand the frustration here, but right now we don't have a solution for this.
We can cofirm that the right team are aware, but we don't have a timeframe for a fix.
As soon as we have an update, we'll let you all know in this thread.
Thanks for bearing with us!