Thanks. I have now managed to clean the glass. It was some dirt on it and the prints got a little better after this procedure.
However, It still seems to print a grid across images. I printed the Blackcat's test A4 and got these results:
(I was not smart enough to scan those, sorry for the quality):
IMG_20160531_204124.jpg
Untitled-1.jpg
If you look closely, 15% Cyan and 15% K gets a faded "grid" all over, as well as the color schemes on the last row get smashed. M and Y is all right.
Any ideas?
Best regards
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