I've just moved into a new apartment and my amps hum like crazy, esp. with the spring reverb on. The amps are fine and the apartment too. The electrician came to my flat and spotted two potential external causes : railway cables at the back of the house and mobile phone antenna next to it. He says he's not sure what is the cause but confirms that the power sockets are nice and grounded.
Has this happened in a place where you play ? Is there anything I can do except from attacking the trains in a wild west kind of way?
Thanks. Have a nice day.