audio file transfer problems from old 5 to new iphone6

I use icloud to backup my iphone 5, and when I got my new ATT 6, I restored successfully contacts, photos etc from icloud to new 6.

Thinking I was done (hah-hah) and wanting to prepare the 5 to sell, I turned off find my iphone on it, put in an unlock request to ATT. This got carried out today, and I got an email telling me to hook up the 5 to my Mac Mini by USB to do an additional backup before resetting the 5.

That's when I realized that the new 6 didn't have any of my music or audio files.

So, I did a backup (successfully, by USB) . Then I properly ejected the 5, connected the new 6 by cable in preparation to restore the backup to it (to get the music/audio stuff transferred over.)

iTunes won't let me do it, repeatedly telling me I've got to turn off find my iphone on the old 5 before I can restore the 5's contents to the 6. I've restarted the 5, reconnected it to itunes, done a repeat backup. Reconnected the 6 --> same error message.

Restarted the Mini, reconnected the 6 to iTunes --> same error, must turn off find my iphone on the 5.

Please guide me on how to retrieve my audio files. I would sure appreciate your help.