i have the bass and treble at half way, and when i turn it up a little bit, something in the back dash rattles and I CANT FIND IT!!! anyone ever had the same problem???
i went as far as getting all the way inside my trunk and seeing if i could find it, and there was nothing loose, the rattle seems to be louder inside the car than in the trunk, but its definatly from the back of the car..........??

its a 2000 tl (if that matters)

 

There is a small plactic box under the back-dash to cover the back-center seat belt ...
knock it ...you will see if anything is loose .... Mine have a loose screw then I have to cut
a hole under the box to remove it .................

 

I have this exact problem. Although sometimes I even get a sound that seems like my rear windshield is rattling loose everytime I drive over bumpy roads, but it is not there all the time...

 

no one has ever had this problem, and found a solution? i guess me and ^ are lone soldiers in this battle!

 

It's probably the rear parcel shelf itself. Take it off and start tightening and padding things. Could be the 3rd brake light, could be the styrofoam blocks, could be the window, could be anything.