I got my billow v2 about two weeks ago, been having alot of wicking issues ive tried about 4 or 5 different coils in it most 2.5 mm id wraps ive done 11,10,9,and now 8....80 vg juice i watched alot of you tube videos also....some ive got to work but then after few hours i get alot of popping and crackling i got fed up and now im on a 50/50 mix