Best way to dampen a micro-vibrating Printed Circuit Board inside an amp? Thanks!

I worked as an electrical engineer for over40 years and have personally designed and tested hundreds of printed circuit boards for both military and commercial designs, and have reviewed many more customer PCB designs as well.  Audible noise coming from a CCA is pretty rare in my experience, but I have seen (heard) it.  If I recall correctly the last time we tracked it down to microphonics in a multi-layer ceramic capacitor.  Had to redesign that part of the circuit to fix it.

@ awise1961  

I can remember doing those vibration tests on a military computer.  System failed almost immediately.  Opened the chassis and the inside was littered with sheared off components, mostly larger electrolytic capacitors.  We had to encapsulate them in silicone.

Thanks to all who gave positive and helpful thoughts, and vice versa.

I put “E Fusing 900 Flex” moldable, non-hardening silicone putty in long lengths under the edges of the PCBs where possible…and yes, the sound is that bit less smeared and clearer, more detailed… so it was cheap and I’m cheerful!    

what is a recommended way(s) to dampen

Apply water ;)