Digital BW, The Print

I've been printing an image in the centre of a sheet, which has a 
wide white paper border around it, on 13x19 paper.

Down one side, in the blank white border, not in the image area, the 
side at the end of the printheads travel, it seems to be dropping a 
trail of ink blots, not in a perfectly straight line, but sort of 
like a row of drunk ants. Each drop is about the size of a large-ish 
pin head

What on earth is this and how can I remedy it ?

I could scan and post or email the problem if my description isnt 
clear ?

MIS sepia>neutral inks and an 1160

thanks
Frank