>What media are you using for the image, out of curiosity? 16GB PNY USB 2.0 Flash drive ("Attache 4"), in a USB 3.0 hub in a USB 3.0 port.
Installed with mkusb 12.3.9-1ubuntu1 with persistence (I've had very good results getting bootable USB drives with mkusb). Are you thinking that there may be some sort of media flaw in the drive?