I have had an IPV4S for a little over 3 months. Just past the warranty of course. The fire button just decided to stop working. Yes the batteries are charged and in correctly. For a period of time if I hit the button hard enough at a certain angle it would work but now I cannot get it to work at all. I use a dripper on it and the way it is made allows liquid to get inside I am wondering if this is the cause. Regardless anyone have any suggestions on how to fix it? I tried taking it apart and cleaning it out. Was going to pull out the board while I had it open to look at the button but it seems to be glued down. Cleaning it out didn't help either.