Very severe interference on the AM band.

[Kevin Kuehn]

Rf interference can ride just fine on any long earth grounded wire, so shutting off breakers doesn't really isolate it much.. Tried taking the radio outside and plugged into a long extension cord, as far from the buildings as possible? If your buildings are metal siding it's almost like being inside a Faraday cage with all the interference being emitted from internal wiring along with the radio signals. What you really need is a long outdoor antenna(as far from building wiring as possible) with a shielded lead in.