Just a bit of general maintenance.
Over the last few weeks each mounting point for the heat shield has let go in turn. The problem is the shield is made from thin aluminium, the nuts and washers that hold it in place are just plain steel ones. Where the steel washer is in contact, the heat shield just corrodes around it and it drops causing a horrible rattle that sounds worse than it is.
Fortunately the studs the shield fixes to are plenty long enough, and you don't have to try and remove the rusted on nut.
Luckily there is a quick and cheap fix. All you need is:
38mm dia x 8mm repair washers
6mm nuts
rubber washers
I placed a couple of rubber washers behind the heat shield to stop it rattling and fretting against its mount/bracket, place another rubber washer against the outside of the shield then the repair washer followed by the nut.