Cannot print properly since LibO5

All other apps print correct (in colour) on my network Canon printer but LibO 5.0 just prints in b/w with a messy top line.
Exactly the same corruption occurs if I save/print the document as a pdf from LibO5.
But print the print previews look fine.
All other applications print perfectly.
OS is Win10
I have looked exhaustively through all printing settings; any ideas?