I just got a V4L PT and my favorite Dijarum cartos from The Mutts Nuts 'Ultra' Atomized Cartridges won't screw on. The Dijarums were different from the other flavors in that they have a hard tip instead of soft. They are the only cartos that I have that won't fit. It seems like maybe the center "post" in the carto is a little too large to fit in the PT. Has anyone else had this problem?
