This message appears in /var/log/errors.log (using syslog-ng) (don't know since when): systemd-udevd[424]: /usr/lib/udev/rules.d/99-indi_auxiliary.rules:5 Invalid value "/bin/sh -c 'test -f /sys/module/usbcore/parameters/usbfs_memory_mb && test $(cat /sys/module/usbcore/parameters/usbfs_memory_mb) -lt 256 && echo 256

/sys/module/usbcore/parameters/usbfs_memory_mb'" for RUN (char 76: invalid substitution type), ignoring, but please fix it.

I don't have a clue about an appropriate fix, apart from deleting 99- indi_auxiliary.rules, and don't know how valid it would be to delete this file. I'm having this strange USB behaviour on 2 machines : Plugging a USB stick may not trigger the 'New device' popup in KDE, while lsblk does list the USB stick. The latter may be connected directly to the machine, or via extension cable or a USB hub. It works half of the time as expected. An this one on one recent host : A USB 3 hub (tried 2 hubs) may not always list its devices, with these errors on resume from a *long* suspend, or on reboot : Jul 31 12:24:22 localhost.localdomain kernel: usb 5-3: device descriptor read/ 64, error -71 Jul 31 12:24:22 localhost.localdomain kernel: usb 5-3: device descriptor read/ 64, error -71 Jul 31 12:24:22 localhost.localdomain systemd-udevd[408]: /usr/lib/udev/ rules.d/99-indi_auxiliary.rules:5 Invalid value "/bin/sh -c 'test -f /sys/ module/usbcore/parameters/usbfs_memory_mb && test $(cat /sys/module/usbcore/ parameters/usbfs_memory_mb) -lt 256 && echo 256 > /sys/module/usbcore/ parameters/usbfs_memory_mb'" for RUN (char 76: invalid substitution type), ignoring. Jul 31 12:24:22 localhost.localdomain kernel: usb 5-3: device descriptor read/ 64, error -71 Jul 31 12:24:22 localhost.localdomain kernel: usb 5-3: device descriptor read/ 64, error -71 Jul 31 12:24:23 localhost.localdomain kernel: usb 5-3: device not accepting address 5, error -71 Jul 31 12:24:24 localhost.localdomain kernel: usb 5-3: device not accepting address 6, error -71 Jul 31 12:24:24 localhost.localdomain kernel: usb usb5-port3: unable to enumerate USB device I can't know if all these are related. I am requesting help in search of an easy fix. Thanks and regards.