Just got one of these, and I really like it but am having a problem. I can't seem to adjust the juice control. Maybe I'm doing something wrong, but when i try and open or close the juice feed, I either unscrew the tank from the MOD, or unscrew from the 510 extender thing, or the whole assembly just spins in the tank. Is there an easy way to independently adjust the juice feed control? Using the stock tank for now, and it's super slidey like all Smok DCTs are