Reboot problem after installing a usb3 dock plus card reader.

Since replacing a usb2 version of one of these with a usb3 one I have had problems rebooting. There are various reports about this on the web some suggesting bios upgrades - and disaster stories following that due to reconfiguring not occurring automatically or only partially during the next boot up.

What happens is that I get a partial reboot but it stops at the point coming back up where grub would normally take over and just hangs there. As the bios has the power button the machine can be turned off and then back on and it boots up normally. No problem powering down and switching back on again either.

Any thoughts? I’m not convinced that it’s a bios problem. The machine came with a number of usb3 ports and some usb2’s too all built in.

John

I had reason to look at /var/lib/systemd/coredump and noticed that plymouthd is often doing a core dump when I reboot, even if the reboot seemed to be ok which from time to time it is even with the usb3 part plugged in.

??

John