Ok so i just got a 510 about 5 days ago and there is one very frustrating problem i have. Whenever i slap in a new cart, i'll get 5-10 good puffs and all of the sudden it will stop producing vapor, and all i get is a lung full of extremely hot bad tasting air... even though my cart has 9/10 of the liquid left in there!!! this is my third e-cig (i have a 901 and 801) and ive never had a problem like this. I stuff my own carts with the poly-fiber and it works fine on my other cigs, but not my 510. And even the carts that came with the 510 do the same thing. The only way i can use me 510 is if i drip, and i know that kills attys pretty quick. Plus it gets tiring filling up every 20-25 puffs... so any advice would be GREATLY appreciated!!!