Kodi 18 - 'cannot save setting' for backup location on usb

[jakenl]

While having issues with the latest updates I decided to update just those packages that were not likely to be the cause of 'not-outputting-HDMI'. I have to do that one by one. So, after a while these packages were OK and a reboot worked fine. I decided to do a manual backup of the system partition, by going into the menu of Xbian / backup /system. The backup starts and runs for a while, but ends with this text:
Cloning root/@, 1075752240 of 1120575251, 96% done (last one with a lot of predecessors with lower percentages)
Cloning subvolume root snapshot @ failed
Operation failed with error E_COPY_DATA

The automatic updates work fine, I had to use the latest backup to get the system back up and running again. For now, I will just wait for the weekly automatic backup before I try to installed the suspected packages.