Comment 4 for bug 1378143

"Track" is preferable. That's because not all audio that ends up in user's collection is a song. It may be university lectures, voice memos, audio books, etc.

iTunes is inconsistent there too. It uses "Songs" as a column heading, but "Track #" for numbering, and "Items" when I look at the summary for a music (yes, music only) collection. They are doing worse than we are! :-)

Anyway, my vote goes to "Track".