We have a xerox colorqube 8580DN which has a job stuck in the que. You can delete the job then 5 seconds later it re-appears.
This is blocking our print que and we have tried the following to clear it.
Uninstall and re-install
Clear printer fault history
We did get a message up on re-install that stated the "job could not be deleted job was finished." or something very similar.
It is connected with a USB and i am running mac sierra OS.
We also had a repair done on the printer and i know the engineer connected via a network connection ip address and i wondering if something has caused this from that? I cant call them back now as out of warranty.