This very well may be a bug however, Ubuntu's package of k3b does not include the Monkey's Audio plugin and subsequently it is not supported. Due to that I am rejecting the bug. You may want to contact the author's of k3b about your issue.
** Changed in: k3b (Ubuntu) Status: Needs Info => Rejected -- k3b-doesnt-support-ape-cue-images https://launchpad.net/bugs/80961 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs