It sounds as though it's coming from the rear, but it isn't a paper jam. The clacking noise is very loud.
Dell explained that the printer was a closed unit, and cannot be repaired, but they haven't done any trouble-shooting as it's out of warranty. My previous experience is that any repair would cost more than purchasing a new printer, which is what I will be doing.
Thank you for your advice.
Many thanks, ***** ***** useful.
I will see if the existing fuser can be reseated, but a new fuser (in the UK) is 75% the price of a new printer (same model but with WiFi capability and iOS compatibility) with toners inc. guarantee, so it's just not worth it.