This started as a little rattle some weeks ago. It now is a lot louder. It appears to come from the drivers side of the bulkhead. The small speaker on the top of the bulkhead appeared loose so I refixed it, and that is not the problem. The shell within the off side wing has a small crack on the bottom edge of the shell, which can flex, but not enough I think to cause the noise I am experiencing. I have done all the usual checks but drawn a blank, any help would be appreciated.
Thanks for your help. Traced the rattle to the bottom of the shock absorber spring. There is a plastic/rubber sleeve on the part of the spring that sits in the cup of the shock absorber. This had loosened to the extent that the spring was in bare contact with the cup. So hit a bump in the road and you have a rattle. I have levered the spring up and sqeezed the rubber piece under temporarily. Rattle gone.