I have three passthroug's one is automatic and two manual. I recently had a problem with all three heating up,and when cartimizer on it will vaper all by its self with no sucking or button pushing. I have plunged them in laptop then USB port and even bought a brand new one from vapor4life and have switched to different cartimizers with every USB I plugged into. So now to vap I have to plug in every time and vap then unplug or it will keep going by its self. Anyone have a clue?