Christian Boltz, with probability one (http://en.wikipedia.org/wiki/Almost_surely) I will not get the time in the foreseeable future for any AppArmor testing. Ian Powell and Sa��a Jani��ka regarding lower-level USB (or libusb) issues: Perhaps on your systems where it does not work there are "interesting" messages related to usb in "the usual log files", cf. comment#34 (dmesg, /var/log/messages, journalctl, whatever-trendy-nowadays...)?