I had a chattering sound from mine.The 3rd row seat is moved by 2 cables from the L and R rails to the motor which is in the center of the 3rd row seat.
The lube dries out over time and the cable makes noise or gets stuck, so I took the cables out "very easy" cleaned them and used a syringe with bicycle cable lube and injected the lube into the cable case which in turn forced all the old dry lube out and then I lubed the cables put everything back together and the 3rd row seat works perfect. took about a 1/2 hour to fix. Good Luck
The lube dries out over time and the cable makes noise or gets stuck, so I took the cables out "very easy" cleaned them and used a syringe with bicycle cable lube and injected the lube into the cable case which in turn forced all the old dry lube out and then I lubed the cables put everything back together and the 3rd row seat works perfect. took about a 1/2 hour to fix. Good Luck