Hi there. By way of an update. A Xerox engineer came to look at the printer. Turns out the SD card was corrupt/faulty.
Replaced now and all's fine.
Hi, and thank you for the suggestions. Unfortunately, I don't think they'll be of help. To clarify, the issue isn't specific to only one Mac on the network. Also, the printer works/prints fine on startup. It's only when left for a while that jobs disappear from the queue without printing. Once restarted and the jobs sent again, they print fine. It's almost as if the printer is going into a deep sleep (though I can still accesss the web interface ...) and has to be rebooted to wake it up again.
Even when in this non-printing state, I can successfully ping the printer, access the web interface as I said, and, to all intents and purposes, everything is fine. My Mac locates the printer, jobs spool for a while (I've seen up to 75% spooled) before they disappear from the queue and ... nada ...
I searched our knowledgebase and found some solutions for printing issues over Ethernet for your device that you can check out HERE.
Our 6700DN (ethernet connected) works for a while after switch on, but then the jobs sit in the queue (spooling at 74%, for example) then disappear. Once the printer is restarted and theh jobs sent again they'll print but the issue returns after a little whil (couple of hours).