Does it sync tracks that you Love in Apple Music? I have liked Apple Music a lot, except for one major thing when I realized that there is no way to view tracks that I have marked with Love, and I'm trying to find a way to get that information out.
That may be what you're talking about, since clicking on the heart icon is how songs end up in "Liked Songs" to begin with...? Note that I only use it in the Spotify -> AM direction, not vice versa.