So I use an Aspire BDC on occasion and with a few different juices have noticed that over the course of the tank the coil seems to "cook" the juice. It seriously thickens up and what was a nice clear juice turns thick and dark and on some occasions clogs the coil head entirely. This has only happened with a couple different juices and I only vape 30pg 70vg juices. Anybody else run into this with bottom coil clearo's?