Sounds like you are using a downloaded soft font that has got corrupted in the printers memory,
When a softfont is downloaded into a printers memory, it creates a lookup table and references each character by its associated label, if this table gets corrupted (shifted) then it will print some or even all characters 1 or more places out,
The cure initially is to turn the printer off and on and see if that fixes it, if it doesnt then you need to reseat the printers memory, if that doesnt fix it then you will need to identify and replace the defective memory
Of course, if could still be a corrupt driver issue that is overwriting the lookup table or the actual font itself, but its less likely than the above solution