Missing spacing.
As before, my Disc Makers experience was generally good. I had previously replaced 1 mix on a CD when reordering, paid for the change, and all was fine. This time I wanted to replace a couple of tracks with new mixes and was encouraged to resend masters of the entire CD with the new mixes included. The new QR code artwork was perfect, but the tracks were now missing the space between tracks that were on the original as sent in by my mastering guy. The explanation Disc Makers gave me made sense, but I should have been informed in advance.