Alan’s in-radio build

“Finished my build, but have one problem. When the amp is cranked to maximum (last mm of travel on pot) it buzzes loudly. I’ve changed the pot but still doing the same thing. Any ideas, please… (later) Thanks for the advice. I rewired all the input side with shielded cable and it’s all working fine now. Originally I had the pot and jack on the chassis so when I changed them to the plastic panel I got the earthing issue.”