loose change sound from the rear

Hello.

When driving over bumps I can hear from back (trunk) a sound which my best description would be: loose change or gold chain jumping on the metal floor in the spare wheel compartment. Imagine you hold a gold chain in your hand and toss it up and down. It is pretty the same noise. I even put my wife with a flashlight in the trunk, but she did not find the source of the noise. Needless to say I toke out everything from the trunk, but the noise is still there. The noise is more noticeable when I put down the rear seats. Something is definitely loose but I can not find it.

I have this problem from very long time but did not pay so much attention. But now after fixing some rattles and creaks it looks like this is the last one and I want to be a 100% rattle-free. I have searched the entire Internet about this and it seems I am not the only one with this problem. I have found 2010 TSX owners with the same problem, but no solution. I found two TSX TSBs (B09-014 and B09-019) with a similar symptoms but I do not think they are quite the same. I do not think the words "clicking" and "popping" apply to my "loose change/gold chain" sound.

Do you have any idea what could be the problem? Thank you.

Take it back to honda if it still under warrenty and get them too look at it. They may have a few come back and found a way to fix it.

No warranty. I am absolutely sure that they will not "hear" the noise or just say "it is normal". It happened before. That is why I want to locate the problem and fix it by myself. If I succeed to locate the noise but can not fix it by myself I will go to the dealer and tell them what exactly to do. This also happened before. The two dealers in my area are pretty deaf and blind when comes to rattles, creaks etc. especially with cars with expired warranty. :(

remove the spare tire, car jack and all the tools and do a test.... Check your number plate as well, make sure is secure and not hitting/touching/rubbing the rear of the boot. Check the speakers, the cables/wires/etc. if noise is still coming from the rear, it could be a nut/bolt rolling about somewhere under the carpet or so, remove to check.

Going to look like the commerical where the guy in the holden dismantle his car and found out its the earrings rattling in the coin/ash-tray.