First of all try another type of media that uses Mk ink.
If it is not there could be your canvas calibration needs to be updated .
If it is there and you are printing at unidirectional at max resolution and you have done a head alignment, paper feed adjustment, and gone through the head cleaning procedure it is most likely a head going out. ( print out a head check pattern to check the nozzles).
Usually when a head is at the end of it's life one of two things happen. Either you will see ink dripping on the print or you will begin to notice subtle banding that gets progressively worse.
john