I'm having the same problem! I do tend to play the whole playlist through several times over the course of the week, but that should be no reason to continue including up to a third (in my experience) of songs I've heard before in the playlist. This playlist does still do a good job of including some unexpected and novel music, but it is most definitely converging toward more similar songs, even those I haven't heard before.
To any spotify devs listening, I think the simplest solution to this is just removing the possibility of repeated songs in the playlist. I hope I'm not sounding demanding 🙂 If it makes any difference, I do pay for premium!
This week's playlist definitely hit a new low for me. It's entirely a repetition of songs I never even liked to begin with from previous weeks. I used to look forward to the list updating on Monday, now I am dreading it. Please just do something about this. There are several options to solve this: put a time stamp on the songs to mark when it was suggested to the user and then make sure it's not suggested within, let's say, the next year. Or just don't suggest songs that have been played by the user before. There's got to be a place where you record how often a song has been played by each user. If last.fm can do it, so can you, Spotify.
Same for me. I have now got the same song for the last 4 weeks, along with about 10 other repeats, most of which were on last week's playlist. I agree with whoever said this makes them think bands are paying for this. Makes the service totally obsolete for me. Pandora doesn't have this problem.
Glad I wasn't the only one hearing repeats. I've had at least 2 songs stuck on my list for 3 weeks in row now, and last week I heard a few songs that had been on there the week or two before and I was really confused. I hope this issue gets solved soon. This is essentially the only way I find new music anymore and I don't wanna hear repeats of songs that didn't make it to my library.