I'm quite new to airbrushing. I'm using a 0.35 cheap airbrush. I'm using pro acryl dark neutral grey as a primer. I think my priming is quite even and good. my problem is with my white paint. I'm using Vallejo game air bone white. I'm thinning it much thinner than my primer and I've experimented with different ratios and PSIs but nothing seems to work. I've disassembled and cleaned the airbrush. I don't think there's any dirt as the priming works perfectly. every time I spray the white, it comes out slightly speckled/dotty.

the pictures with multiple pieces was my first attempt, I did a thicker paint with a lower psi for the highlights, then tried to blend it with a slightly thinner paint but the PSI was too low so it turned out quite bad. one pic is the highlighting and the next was me attempting to blend.

the spoon is a ratio of 1 thinner, 2 flow improver 4 paint at 35 psi. this is the best result I could get on a spoon. I know I could go very thick on the white paint to hide it but it becomes a problem when I want to preshade and blend.

for the skirt gunpla piece, I did 2 thinner 1 flow improver 4 paint at 30psi. I am priming, then doing highlights in the middle of the sections, then doing a thin coat over it all to try and blend it. I can't go too thick or the highlights will be hidden. I tried to highlight the middle of the bottom parts but the blending isn't going well. I want to blend it like the white in the screenshot.

any advice is appreciated 

Is this amount of speckling normal for white acrylic?