HP Latex 315 print quality

Hoping someone can shed some light, please see image attached. I'm printing on Drytac Retac substrate, and the brighter colors tend to come out with fine lines. I have used the sponge kit to clean, lubricant, and performed the internal print head maintenance function of the printer.

Thanks for the reply! I did the test and it printed the attached. Can you advise on the next step?

#1 Based on your diagnostic print you would need to at least change your Number 2 Printhead - Light Cyan/light Magenta Number 6 Printhead - Magenta/Yellow It is a little hard to see quality of the other heads from your photo but these 2 printheads being changed would be a good start. Do them both at the same time so they get aligned with the least amount of media wastage.

#4 Thank you!

#5 Thank you !!