Have a metallic/rattling sound under my car while idling. Don’t hear it while driving.
Any clue???
2010 Mitsubishi Outlander
Here is link to sound file
Check the heat shields on the exhaust. They could either be loose or there can be a stone up between the heat shield and cat.
Hard to say definitively from that sound clip, but I second knfenimore’s recommendation of a loose heat shield as the most likely culprit.