I haven't seen it mentioned in this thread, but if you are decanting, be sure to let the decanted paint sit in the jar, uncovered for at least a half hour or more to de-gas. Perhaps more. It may help to cap and shake the bottle occasionally. Pressurised gas remains entrained in the decanted paint. Sometimes, if you give a bottle of decanted paint a stir or agitate the bottle, the paint will bubble up and overflow the bottle. When decanting, do not fill any bottle to the top for this reason. Decanting works well, but if the gas has not all escaped from the paint, you may encounter problems when spraying. When the paint passes through the body of the airbrush it encounters a low pressure area (at least, in my Badger 200 siphon feed, it does) which causes any remaining trapped gas to be expelled from the paint, screwing up the flow action within airbrush, and generally making a mess at the tip causing splatter, etc.