Whenever I go past about 50 mph my S70 starts a rattling noise that does not stop until under 50 again. It is like something is loose, maybe in the dash as it seems to come from that area.

In a garage recently the mechanic checked everything like suspension and brakes. They are sure there is not a safety issue, but they could not locate where it was coming from. It is a terrific car but the noise is a bit annoying and I want to get it fixed if possible.

Thank you to anyone has any ideas about this!