Hi, Guys
The CMYK print looks fine. If there are any lines missing, some of the nozzles are blocked. I cleaned my Roland yesterday (we had renovators in here, so everything covered in dust!) and printed a test sample afterwards. The result is the same, CMY perfect, K slightly wonky – and missing a few lines in my case. Print quality is still perfect. though. I have noticed the missing lines on the K for some time now. It does not seem to deteriorate at a great rate. We do a lot of printing, right now I,m babysitting the printer, with about 25 or so files ripped, still to print about 40m! – all for tomorrow (gulp) 
PS Did you do a manual clean, or just the one from the keypad? Also, if you have flush cartrages, give it a go if manual cleaning doesnt work.