Walmart, 97 cents, for Vibration Control

I don’t know about pipe-cleaners, but this is what I use...

Light anti-vibration

Medium anti-vibration

Heavy anti-vibration

NAD C-series top and bottom-side anti-vibration (to look like NAD Master-series pucks).

A collection of 3D models, also showing one with neodymium magnet embedded.

I 3D-print these and (as can be seen) combine with other vibration-reducing materials (golf practice balls, squash balls, rubber slip-resist pads, magnets, etc.) to suit each application.

Here we see the NAD C-series pucks in action

Makes the Classic series look more like the Masters series.

Another good make-shift ant-vibration solution is Velcro - that’s what's between gear racks and turntable plinths. Get the heavy-duty Velcro, (supports more weight without crushing) and the other great benefit is the plinth can’t be pushed or slid off the rack by accident/kids/pets/etc. My DIY-conversion IKEA racks can actually be lifted and carried around by the butcher-block plinths (if the rack is empty). 

I would not recommend 3M "Dual-Lock" - that will have little/no anti-vibration effect. Dual-Lock has it's purpose, I use that on the motorcycles for mounting cameras, camera remotes, XM antennas, etc., but if you're looking for vibe-control don't mistakenly buy "Dual-Lock" for that. You also don't want "Low-profile" for anti-vibe because you want the highest profile available.

This reminds me of another anti-vibe solution that’s on the IKEA racks... equipped with soft rubber casters to help isolate from the floor, and enabling easily spin and move (to make cable connections) - very convenient with a 73 Lb. amp on the bottom shelf.