Bushings for rack-mount equipment

Hi Tiroth

You should be able to get plastic washers from any pro audio/studio or music shop or dealer, and remember to mask the rackstrip with insulating tape as well.

However, If you are getting an earth loop or similar in a piece of rack mount kit it is usually caused by a fault in that piece of kit, as it is designed to be racked with other equipment and this should not cause problems.

DO NOT try removing any mains earth present, as this could be dangerous, but you could try disconecting any signal earths on input or output and see if this helps.