Sometimes they have a bad wick strand (my guess) and that strand "pops". Prompted my username and was one of my 1st posts on ECF. When I switched atties, the next one was better. Most of the answers I got back were "Dude, those are the BEST ONES!"
Make sure you are:
1) Blowing out the primer on a new atty
2) keeping it wet but not flooded.
Some brands may do this more than others. I sometimes wonder about wicking materials from different vendors....could be moisture on the wick too. The wick isn't supposed to fry, or dry burning would kill em all.
If it quits wicking the
juice into the atty, the strands are gone/clogged. See/search Dry burning, and DRIPPING.