Got an 18v Dunlop power supply for my Tri-Logic 2 pedal recently and it's making a god-awful hum which is clearly audible even at low listening levels. It's a high-frequency 'digital interference' kind of noise, kind of similar to a ground loop noise, which is not there when the pedal is powered by batteries. The Tri-Logic is the only pedal I use, I'm playing a Fender Jazz straight into the pedal, which then goes into my audio interface and then my Mac. Works fine with batteries, makes evil hum with adapter. Anyone have any ideas?