Got an annoying problem with a rattle, which seems to be coming from the perforated tube inside the rear box.

It only does it when it's cold, i.e.first thing in the morning, but it is bloody annoying!

Has anyone else had the same problem?
Also does anyone know about warranty on the box as i might try and get it changed as a last resort!

Any help/advice greatly appreciated.

Cheers
Simon.