DC hum

[LoRydr]

My jemini distortion pedal makes a hum when powered by the 9V wall wart. Not a 60 cycle buzz. A somewhat higher tone. Not from battery power. Just a bad power supply? Or can some kind of EZ style of filter be rigged?

[Hellbat]

Put some tape over the battery connector if you don't keep a battery in when powering with the adapter. It could be shorting out to the chassis. That happened to me with my ISP Decimator pedal.

[VitaminG]

have you tried it with different power sockets?

[straycat]

PC in the same room, compact curly Q lights being used.?