On Sun, 7 Apr 2019 20:19:21 +0100
R D S wrote:

I pulled a pendrive out of our Humax Freesat box, rolled my eyes as
usual at the remove safely error popup.

Plugged it into laptop (Ubuntu) though, heard the usual noise as if
it had been recognised but it isn't visible in files.

Gparted doesn't seem to see it.

Smartmon says "Read device identity failed".

Is it knackered?

Does it appear when you run lsusb ? That will show if the controller
is working, regardless of whatever file system may be present/readable.