Core Rot at Apple generated more page hits than any topic ever presented here at MacPerformanceGuide.com. Many bugs remain extant; I have time to report only a few.
But Apple does fix bugs and it’s important to acknowledge progress—
Fixed — duplicate or triplicate tracks on iTunes import
As I have a contact on the iTunes team, I recently reported a troublesome 'import' bug: iTunes was creating duplicate tracks while importing a CD (or triplicate tracks if imported from files already copied from the CD onto the Mac).
I provided a ZIP file that made reproducing the problem 100% guaranteed. In general most bugs tend to be intermittent and thus hard to document with a test case, so a 100% reproducible case is a big help in getting a fix done.
It turns out that the duplicate/triplicate track bug was related to the presence of playlist files on the CD, as shown below.
This was a commercial book-on-CD and thus it’s a little baffling how a bug like this could exist in version 11 of a program for such fundamental functionality, but there it was. It had discouraged me from using iTunes for a few years now (I still buy most everything on CD, almost always books). Finally, the bug has been fixed and that is satisfying.
Files on the CD that included two playlist files, apparently responsible for the 2nd and 3rd duplicate:
llcMule:~ lloyd$ ls 01.mp3 12.mp3 23.mp3 34.mp3 45.mp3 56.mp3 67.mp3 78.mp3 02.mp3 13.mp3 24.mp3 35.mp3 46.mp3 57.mp3 68.mp3 79.mp3 03.mp3 14.mp3 25.mp3 36.mp3 47.mp3 58.mp3 69.mp3 80.mp3 04.mp3 15.mp3 26.mp3 37.mp3 48.mp3 59.mp3 70.mp3 81.mp3 05.mp3 16.mp3 27.mp3 38.mp3 49.mp3 60.mp3 71.mp3 playlist.m3u 06.mp3 17.mp3 28.mp3 39.mp3 50.mp3 61.mp3 72.mp3 playlist.pls 07.mp3 18.mp3 29.mp3 40.mp3 51.mp3 62.mp3 73.mp3 08.mp3 19.mp3 30.mp3 41.mp3 52.mp3 63.mp3 74.mp3 09.mp3 20.mp3 31.mp3 42.mp3 53.mp3 64.mp3 75.mp3 10.mp3 21.mp3 32.mp3 43.mp3 54.mp3 65.mp3 76.mp3 11.mp3 22.mp3 33.mp3 44.mp3 55.mp3 66.mp3 77.mp3