[cups] "Filter failed" - usb connected thermal printer

[Ianseeks]

Hi

My printer has been working for ages but suddenly from this morning it has stopped printing. (my CUPS software versions are listed below).
Cups admin finds and configures the printer (identifies it as a Sewoo LK-T12 but its a Partner RP320 and has been using the RP310 driver) with no problems but when i try to print it gets the message (under "State" column) "Stopped, filter failed" on the "Printers" page where is lists the jobs.  I've looked in the error.log but i can;t see anything obvious apart from lots of recurring " Expiring subscriptions... " messages, but then again, i don;t know what i'm looking for.
If i give it an incorrect driver, it prints garbage so it physically works.

Anyone have any ideas?

Regards

Ian

libcups2-2.2.6-222.1.x86_64 
cups-pk-helper-0.2.6-2.2.x86_64 
cups-2.2.6-222.1.x86_64 
cups-config-2.2.6-222.1.x86_64 
cups-client-2.2.6-222.1.x86_64 
python3-pycups-1.9.73-1.2.x86_64 
libcupsppdc1-2.2.6-222.1.x86_64 
libcups2-32bit-2.2.6-222.1.x86_64 
python2-pycups-1.9.73-1.2.x86_64 
libcupscgi1-2.2.6-222.1.x86_64 
cups-filters-1.17.6-2.2.x86_64 
libcupsimage2-2.2.6-222.1.x86_64 
libcupsmime1-2.2.6-222.1.x86_64 
python3-cupshelpers-1.5.7-12.1.noarch

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