First let me say this is the best mod I have ever tried. I purchased my vv REO two weeks ago and I liked it so much I just placed a order for a REO mini 2.1 white. OK back to the problem. Last week I noticed that my cartomizer wasn't working right I kept getting blank hits so I threw it in the garbage, went to my local store and picked up some new cartomizer and a atomizer but same problem blank hits and sometimes I had to drag on it very had in order for it to work. I thought maybe it was a problem with the cheap cartos I purchased at local store or that maybe I had some bad batteries so I purchased some new batteries and a pack of boge carto and still the same problem and now it even burned out 2 of my cartos even though I primed them really Good. Can anybody tell me what's going on?