I've been vaping for a couple months shy of 2 years now. I used a SB for quite a while, then acquired some 3rd gens and stopped using it. Well Both of my 3rd gens are out for repairs right now, so I've came back to my trusted SB. There seems to be a problem though. I can use it at 3.7 with an 18650 just fine. When I put to 3v batteries in it wont get any juice. I've checked it with a multi-meter. Voltage is just fine with an 18650, but with life PO4's I get nothing. Same with the tenergy 900MAH's. I can't think of anything in the world that could cause this. I have 4 sets of the Life PO 4's and two set's of the tenergy LI Ion's So It's not just one set doing it. Help please.