Do you put a single sheet in? If you do, put a stack of 10 or so.
Is there play between the guide rails? Put 10 sheets in then adjust.
Does the paper have a slight curl or are the corners bent?
My old Lexmark chewed up paper at regular intervals if I didn't treat it
with a bit of care - I've given up using it with B5 paper - I've got it set
up for A4 and that works fine.
