As with attys, every carto is unique. Try overfilling it and blowing out the excess to make sure you have it good and soaked. I gave up cartos and went back to attys for that exact same reason. Put a bit too much juice in -- flooded and leaking. Not quite enough -- burnt taste & low vapor..... some cartos are better than others and some are worse.... and like i said, each one is unique...the variations in manufacturing can be anywhere from minimal to drastic. Try another carto and if that doesn't work, try another brand if you want to stay with them. If it turns out to be just drying out too quickly from vaping heavy, get a drip tip for your model cartos and drip them like an atty.