Engine vibration making catalytic rattle

Hey all. Figured out my catalytic is rattling, though not from inside, but the heatshield part. Seems when I turn my A/C on when the engine is cold, that is usually enough to make it rattle. Sometimes it just rattles no matter what. What is the best solution? Motor mounts? Put a bracket brace on the exhaust pipe somewhere? Tack weld the heat shield onto the catalytic better? Thanks

check the rubber mounts that hold the exhaust in place.

Have you banged against the shield with engine cold? Had gravel trapped between heat shield and cat on mine.

I'll check, but it's pretty clean under there. Seems to be the motor itself causes enough vibration to rattle the pipes, and cause the noise on the cat. I'll need to look at the rubber mounts (thanks, didn't even think of that). Also wondering if I need to change out the muffler gasket to the exhaust pipe. It's kinda rotted. Drips water, though I suspect that's due to the 100% humidity here.

Solved it: where the rubber mounts attach to the frame, the bolts were missing, and that weird, weird brace for the exhaust was rattling on the frame. Got some M8 bolts and reattached to frame with loc-tite Thanks for tips everyone