jAAAmes

lately ive been noticing a hissing noise while driving, whenever id accelerate it would get louder, i was scared that there was something wrong engine-wise, as the sound appeared to be coming from somewhere right behind the radio. however i found that the problem was actually that rubber grommet around the shifter, and what i was hearing was just road noise. its not making a proper seal. i tested it by removing the boot and pulling up on it to make a seal as i was driving, and the noise completely went away. i was really relieved it was that simple, but now my question is, what would be the best way to make sure it gets a complete seal?