My Zmax has just started to shock my lips while trying to fire. I push the firing button and I feel the current running through the tip. I have a Kanger ProTank on it. I tried changing the battery out, cleaning the Zmax and tank parts, restarting the Zmax, and changing out the atomizer. It doesn't do it all the time. When it does do it, which is probably 1/2 the time, the device doesn't seem like it is trying to fire at all, the current is not engaging the atomizer but running through the drip tip instead. I do not have and other tips that are metal so I can not change out the tank to see if that is the problem. Anybody else have this issue? The device has never been dropped.