Hello Petur,
How long has this been happening? Have you been experiencing this for a while or did it just start? Your answer to these questions could be very important. It's rather difficult to see, but I assume the third pattern from the right is supposed to be the Lt Lt Black, is that correct? if that is the case you do have a gap in the pattern in the seventh line from the top, slightly right of centre. Also one in the Lt Magenta, eighth row from the top, left edge. Both of these together could possibly have caused this issue.
Gary