I have that same problem.... same basic setup (attys from VaporKings... batteries are my originals from SmokeTip).
I'm wondering if it has something to do with the bottom of the atty getting gunked up with
juice. I never really had an issue when I was using dekang PG stuff, but since I've been on 70/30 PG/VG from Viking its started happening.
I find if I clean the atty out really good (boil in filtered water) the issue goes away for a while, but only for a day or two.
I've been using the body of a cartomizer cap with the end cut off to slide up the atty and cover the whole, but with limited success. The trick is not to cut off air flow completely, just enough to effect the draw. It's a pretty fine line. I was using my thumb for this for a while, but I noticed I was getting
juice on my thumb this way, which I would rather not.
I'd love to hear if anybody else has a better solution to this problem (apart from just buying another manual battery, which is the solution that is going to get implemented pretty soon).