[DrivingPassion]

When going over small bumps or unevenness on the road, there is a distinct clicking sound emanating from the rear speaker area.
It sounded like it is coming from between the black felt wooden (?) platform which the speakers are mounted and the metal cover from inside the trunk.

I cannot reproduce it at will. Usually after about 10-15 mins driving, the sound will show up when driven on a service road at 35 mph or slower. It's most distinct in an indoor parking lot.

Any idea what the root cause is? I unlocked the rear seats and laid in the trunk while another person drove the car and I could pinpoint the sound coming from under the speaker area.