I have been seeing this with both the 18650 and 18490 batts I've been using. Got my Provari end of December and since mid Jan I have been getting the blinking at 3.8-3.6v. From what I read it is not supposed to start till 3.5v. Cleaned the device from top to bottom w/ q-tip and alcohol. Even cleaned under the spring but I have the satin so the coating isn't an issue. I even bought 2x 18650's but same issue. I just find it odd that 2 new 18650's would start blinking at 3 hours... the other PV's I use them in give me a good full 2-2 1/2 days of vaping. I also assume I have the new spring since I got it in December. Anyone have any other ideas? I have been removing and reinserting the battery and that seems to work as long as I do that every few hours. I just hope I am not damaging the batts or PV by doing so. Or worse yet, risking battery explosion from using batts that the PV said needed change 