Okay, I have just done some more online research and I have found this bug relating to libcdio: https://www.mail-archive.com/ubuntustudio-bugs@lists.launchpad.net/msg06384.html
I don't know enough to make a guess as to whether this exists as the same double-free bug, but if so, then the problem lies with libcdio, and the fixed version was uploaded to experimental just a few days ago. Best, Jack
