try disabling bidirectional support - this should work wonders! (im sure someone would have recommended that) - its a known issue with the drivers on this model, apparantly the printer 'talks back' to the driver automatically so doesnt need the bidirectional support to be enabled.
Don't know if this will help anyone else but I just had a problem with one of these printers dropping offline. The solution that worked for me was to remove SNMP from the port settings. Took me a few hours of faff to pin that one down - hope it helps someone else.
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Try using the universal print driver v5