Yep. It's a harsh "crack/click" sound rather than a rattle TBH. Only happens when the chassis flexes somewhat.
Think i used to get this when pulling off the drive in my ep3 , seems to be windscreen movement ?
Clearly a cut and shut. Should have kept the first one mate.
Certainly isn't the seatbelt clasps.
Could be a poor spotweld..finding it is another issue.