I hope this is an appropriate place to post this question since it's more about how to connect the device than about Argyll.... I've installed the ubuntu (debian I presume) package that puts the 55-Argyll.rules file into /lib/udev/rules.d . So I've tried putting it in /etc/udev/rules.d but to no avail. Is it because it's a "B" rather than just a "94"? I assumed it was sufficiently similar that it would work anyway. Typing "udevadm info -a -p `udevadm info -q path -n /dev/sdb`" and "lsusb" don't seem to list the device either. Grateful for any help, though I realise this more of a Linux issue than an Argyll one. phoenix