I'm a little worried about it as this started around a month ago. I never had a problem with higher voltage (up to 6.5) or a l.r. on a 3.7. I can't seem to last more than about an hour on a l.r. with liquid that has no throat hit. I can hardly vape liquid that has a TH on l.r. I have bought some Biotene products for my mouth and the dryness, which help when I am not vaping. The roof of my mouth and parts of my tongue get sore. Why all of a sudden. Could it be the attys....I have only used genuine joy for reg and l.r...always. With reg attys and a juice that is somewhat mellow I am just fine...all day..but I do miss the warmth plus I have 35 brand new l.r. attys. Suggestions help please and thank you.