Artist/Album/Song browser missing lots of track

[dfordivam]

If I just browse through the artists I see lots of missing artists.
Even the artists which are listed have missing album information.
Similarly the listed albums have very few tracks, most of them are missing.

But if I play the complete album (by pressing enter), then the playlist gets the whole album.
So I think it is an issue with the browser.

I am using nixos with mushu 0.1.1, mopidy 2.1.0.
ncmcpp works fine with mopidy.

Note: I get the message "This shouldn't happen" many times while working with the browser.