Without sounding rediculous, the "ghost" sounds more like something you would hear on Scoobie Doo, like uhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh, coming in, fading out, sporadically. It does not happen everytime. It can also be described as a "humming" like mmmmmmmmmmmmm or a "howling" oooooooooooo (deep and loud coming from the pit of your stomach).
When it does happen, it seems to happen after the car has been running a while and after you let go of the brake and accelerate, i.e., after a red light, usaually for a short distance, the most right now until the car reaches 25 mph.
If and when it happens and you apply the brake, YES, it does kill the noise.
I know this ghost noise sounds rediculous, so please don't kill me with any jokes. I would not believe it until I heard it myself.
I think it has to do with my tire rotation and the guy saying he has to replace the bolts. Something is going on inside one of the wheels, i.e, the cover, rim, disc brakes, etc. I don't know how it works inside there so I cannot fully think of how that noise can develop from the wheel rotating after a stop and why the brake dampens it.