So I had the car in the dealership (Pepe Infiniti, White Plains, NY) for the door rattles, rear deck rattles, pulling to the right and a few other things. They schedule the car for a 2 day repair. I finally get the car back after 5 days! (They gave me an I35 with less than 5000 miles on it for a loaner so I was patient) They performed the TSB for the rear deck and the doors. Said my car was within spec on the alignment (Still pulls slightly though) They said everything was great and patted themselves on the back for a job well done. On my way home (75 miles away) the exact noise that I put it in for becomes immediately apparent...major bummer. So although I could bring it back to the dealer, let me turn to the forum first. The noise I hear is a squeaking. Almost sounds like the leather is rubbing against something. It comes from the passenger rear door panel. It happens whenever I hit a bump, rough roads, or bass heavy songs. It appears to come from the upper right hand corner of the door I had a passenger back there feel around and by pressing on the corner the noise seemed to stop. I could not convince my passenger to stay in the back seat until my lease runs out in 3 years so now what? The noise has now appeared in the front passenger door and to a lesser extent, the driver's door as well. It almost sounds like my speakers are blown in the front because of the buzzing but you can press against the liner to make it stop. I can't reach the rear door when driving so that is the noise that really bugs me. Any suggestions? These squeaks, creaks, rattles or whatever they are to be called are my only real complaints about the car. But they are ANNOYING!!! Help!

 

There is a thread here about how to remove the door rattles.
I followed the instructions and was able to remove all the door rattles.
It sounds like this might work for you. I ended up putting some
foam insulation tape around the speakers in various places
and that fixed some rattles. Do a search and you will find it.
I will look now for you and try to point you to it.

2003 Twilight Blue Sedan 5AT, sunroof, Graphite Leather,
splashguards, GG red 8 wire Hypergrounding kit, 350Z intake duct, Stillen Hi-Flow Airbox

 

Found it!!! Do a search on "**FIXED ** RE: Rattles, Creaking in G35 Sedan" There is a pretty detailed explanation of how to fix it.
I found pics of the fix on the thread when I fixed mine.
I would have thought that this thread would have been added to
the DIY section of g35driver.com
IT BELONGS THERE! Moderators care to move it?

2003 Twilight Blue Sedan 5AT, sunroof, Graphite Leather,
splashguards, GG red 8 wire Hypergrounding kit, 350Z intake duct, Stillen Hi-Flow Airbox