Why do I have to keep hunting for a good temp and watt setting on my Jac. I'll have it set where I like it, and after awhile without the numbers changing, all of a sudden it's too hot. For instance I was vaping at 375F, and 35 watts, then wow, way too hot. I went in and started re adjusting and ended up at 335F, and 20w. After awhile, I'll have to go raise it back up again. I'm using SS wire. If I put in a new coil the same thing will happen again in awhile.