Got one of these about 2 weeks ago. It works but it feels like the build quality isn't all that great next to my subvod. Especially when it comes to the airflow adjustor which feels very loose like it wiggles slighty if ANY upward pressure is put on it. Is this Kanger quality control or should I see if I can get it exchanged? I'm OCD about these kinds of thing. Anyone else own one of these?