Put this together today but having an issue. When powered on and engaged I get a loud hum. It sounded like an errant ground somewhere. I tested the input by testing with my meter and it is connected to ground. Can't seem to see a reason for it unless I'm missing something obvious. I examined all the solder connections and they look good with no bridges. I haven't checked parts values yet as I don't think that would cause this issue.
Thanks!
Thanks!
