Exhaust vibrations/noise

I have had for some time some exhaust noise/vibrations, and decided to buy a new exhaust. However when I checked the exhaust I couldn’t find any holes or any bad rubber holders. I decided to not change it and investigate some more.

The noise increased and it seems like the exhaust has been lying on some metal making the noise marked with red.

I can turn the rubber holders of the exhaust to remove the sound, but how can it be that this is hitting the metal: The image shows the one that has been turned.

But this holder and also the other rubber holders look to be fine – to the best of my knowledge. Is there supposed to be rubber on the metal the exhaust is hitting? Or how can this happen?

After turning

It seems now the noise has disappeared, and it has not been turning back. I find this really weird how that can happen. Is there some issue with the rubber exhaust hanger? Is it general that they make this noise polos from 2013?