When you store your AB for any given period of time, dust settles into the interior/exterior of the AB. Next time, may I suggest a blowing through the AB with lacquer thinner prior to the job. You've got me to use dish soap with the AB, the dish soap if allowed to dry and or settle can indeed clog the inside of the nozzle tip.
Mind you, don't stop using the recommendation that you gave me in regards to the use of dish soap added to your AB paint mixture as that definately helps from the splattering effect. Although, if you were building a Luftwaffe plane, that camoflauge motif intentional/un-intentional would have worked to the extremes. LOL! No one no matter how good they are, would ever be able to replicate that! LOL! Another fix would be to purchase a tube of "Super Lube" by Iwata and spread that within the AB housing. If you have questions on the "Super Lube" by Iwata, I'll be happy to help you with this. I've been using "Super Lube" religiously.
At my build rate, my AB use is everyday. Only on this build, I have not used the AB for more than two weeks as the Zoukei Mura Horten HO 229, being a visible (See through) kit. I'm having AB withdrawals. LOL! My brush(es) I have three, (NEO Iwata gravity feed, NEO pistol grip TRN1 gravity feed, and my Harbor Freight Tools siphon feed) will need to be blown out with lacquer thinner prior to use. Think of it this way. Most if not all people that owns a car needs to have a oil changed at some point. It's basically a pre-prep prerequisite of using the car. If you don't maintain your vehicle, only bad things can happen. The same theory applies to all things mechanical.
In my youth, I used to rebuild old classic cars, the more moving parts you'll be dealing with, the more possible breakdowns occur. Just like your AB. I can speak (Forgive me for being too forward sir, in all respects to you) for the both of us as I recall that you own the NEO Iwata gravity feed AB as well. If not, please except my apologies. This tip should be able to work for you. Let me know if it doesn't, we can then work step by step on this issues of splattering on the NEO Iwata.
Another note; I break down my AB after every use no matter how small the job. It's just good practice-habits in knowing the internals of your AB If not only to throughly clean and maintain your tool. The only issue with the cleaning process that I use is that I can damage my needle and tip, remember the more moving parts, the greater risk of the breakdown. But if you're careful/anal like I am, the chances of a breakdown should be minimal at best.
Toshi
On The Bench: Revell 1/48 B-25 Mitchell
Married to the most caring, loving, understanding, and beautiful wife in the world. Mrs. Toshi