I can not speak about your specific problem with the Rackbrute but i think it's a pretty common problem for hardware in general. I used to work with a Digital-Video-Tape-Machine (HDCamSR) from Sony wich is a realy expensive piece of technology (around 25k Euro). This thing was wobbling around when i we're pressing buttons or ejecting/loading tapes. A piece of beerfelt was the Bavarian solution to fix it. Some behringer stuff i own is wobbling and other Hardware too. I think the Problem are not the plastic feets underneath, Sometimes the housing ist not 100% straight/flat and quality controle is poor.
-- Max_Modular
It’s frustrating as this is quite ‘expensive’ to me and I expected a premium experience.. but it’s hard knowing the line of where to say ‘ah, I’ll deal with it..’