My new coils came today and I've tried three of them but none are giving me the proper crackle. I checked the codes and they are genuine so I'm now wondering if it's my nautilus that's at fault? I get a very slight crackle but if feels like when a coil is coming to its end and it's not satisfying. The difference when I then vape using my GS air tells me it's not right. Has anyone any idea what could be wrong?