So long story short, bought a 2 batt auto kit from myvaporstore.com, aewsome love it. Wet a battery, ruined it and ordered a new one from same site. Slightly different looking end 4 holes instead of 2 but worked great right from being for like 5-6 hours, recharged it, started getting real hot on charger, so sent it back for an exchange, get my 2nd one and no hot charging issue but i do get this....Start using with refilled carto and works fine for maybe a half hour, then whenever i take a drag it seems to work for a second then i feel cold air coming through (without vapor) and the led stays lit for 5 more seconds, this happens consistently, really annoying since this happened with the first battery too. however if i just take a drag from the battery for no matter how long (2, 3 seconds ) the led seems to brighten and dull normally. I guess my question is, is there some kinda new micro chip that senses too much use and cuts you off, does it know when a carto has been reused? I have already tried readjusting the tip for better connection and nothing. I have no clue and am debating ever getting another battery from them again