Looking at the photo, I don't really see anything that would make me believe there was anything wrong with the calibration or that the head was dirty. Instead, it looks like you've selected the wrong print mode in Flexi (this is an assumption, since they "give" you a copy when you buy the printer). I can't remember the steps, to change it, though- it's been a year and a half since I used a Mutoh.
Of course, a thorough cleaning isn't going to hurt anything.