Hi Joe. I too had a malfunctioning English Muff’n. It started to fade in and out ( output volume up and down )until it quit altogether. I switched out the tubes for 2 new EH tubes and it still didn’t work. I couldn’t figure it out so I sent it away for repair. It was returned fully functional. The repair shop said the tubes were shot. So the replacement tubes I tried were shot right out of the box. I ended up wasting close to 100 bucks with new tubes shipping and service charges. If I had the tubes tested I could have saved some money. So dont assume the tubes you bought are good. Go to your music store and get them checked to make sure it’s not the tubes. Other than that little bit of advice I can’t really help. Good luck, it’s a great pedal when it’s working.