It seems that the USB backend tries the wrong printers. It tries /dev/usblp0 and /dev/usb/lp[0-15].
However, udev on my machine creates the printer as usblp[0-...]. There are no special rules, so the device name seems to come from the kernel. Thus, the second printer is never found. -- problem with USB backend https://launchpad.net/bugs/49670 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
