Here is the reply from
joyetech that VapeNW posted on ecr
We have seen some threads and concern about the humming noises coming from the eVic-VT units. We sent a message to our rep yesterday afternoon and we received this message.
Directly from our Joyetech representative:
eVic-VT has some characteristic sounds in operation. These sounds are very low in volume, and can typically only be detected by holding the device close to the ear. eVic-VT boost circuit inductor emits a continuous high-frequency buzz, and the switching system that detects atomizer resistance produces an intermittent ticking noise rather like that of a quartz watch. These noises are normal, and should not cause concern in any device that is otherwise functioning normally.
When the device goes into standby after a period of 3 minutes without use, or if the power button is pressed 5 times, all such noises will immediately cease.