I understand your problem friend.
Those who say this is not an issue have forgotten several factors.
I vape late at night, my girlfriend is the world's lightest sleeper, she gets mad if woken up and I get grief.
If you are using a substantial vape kit they can make quite a noise, especially when fluid crackles and pops and occasionally explodes on the coil.
I have found that the only solution is to take a thin sock, fold it in half lengthwise, and then loosely wind around the tank.
This reduces sound by 70 to 80 percent.