Check the reliability of the clamps.
Replace very noisy exhaust pipes.
Inspect the exhaust system with a lamp to detect holes, rusted parts, and worn areas.
Inspect the catalytic converter for external damage such as dents and cracks. Tap the catalytic converter with your hand - if there is a pulling noise, the ceramic base of the catalytic converter is damaged and it must be replaced.
Caution: The catalytic converter may be hot.
Check the rubber holders for porosity by twisting and stretching them and replace them if necessary.
Shake the entire exhaust system to see if it is knocking anywhere. If so, loosen all the bolts, straighten the exhaust system without tension, and tighten all the bolts again.