I added a song to my play queue using "play next" on my iPad (with chromecast) a while ago.
After it is played, it is not removed again. The next occasion (like the day after) I start playing a song, it gets played again second... This has been going on for a while now - and it is a really annoying song!! (Gipsy kings)
I have never gotten "play next" to work well on my iPad, but this new bug is very hard to live with.