A different solution for me:
I tried everything suggested including a complete un-sync then re-sync, even a complete restore, but nothing worked.
Then I figured out what was causing the 13019 error for me.....a voice memo!
Just last Sunday, I ripped some songs from old CD's that had been gathering dust in the closet. The day after, I noticed that iTunes didn't find album artwork for everything, so I launched a program I've had for a while called FixTunes (for Windows) that tries to automatically find missing album art. If it is successful, it makes a note in the comment field of the song that says
FIXED . If it can't find the album artwork/metadata, it stamps
SKIPPED in the comment field.
FixTunes saw the voice memo as a song which it couldn't match back to any known songs, so it stamped
SKIPPED in the comment field. All I had to do was removed that text in the comment field then no more 13019 error!
I hope this helps someone.