Thanks to all for your help
The banding i am talking is not like lack of ink, etc... is more like strips of diferent glossy aspect in the direction of the feed paper.
In the past i have only printed normal fotos without big parts of deep black and using the 720pp+High Speed and never have seen this problem.
But yesterday a made one picture with big parts of deep black and use the 1440pp+High Speed and i get that bad quality in the black area.
So i have made some tests and discover the problem
The problem is the
High Speed mode for that kind of pictures.
I made a test for 1440pp and 720pp with
High Speed mode and have the problem
and made another ones at 720pp and 1440pp without the
High Speed mode and get fantastics prints
So for all most every pictures i can use
High Speed mode with great results.
But for pictures with big parts of deep black or critical quality for now on i will not use
High Speed modeRegards,
Pedro