Not related to interference but for safety - I was just looking at the 4th photo in post#1 ('dsc_0004.jpg') and noticed that the blue and brown cables going to the toroidal power supply appeared to be connected to incoming cables using male/female spade connectors. There looked like there was exposed metal on at least on of them.

If they are indeed the mains supply cables I don't think this is a good idea. Either put some heatshrink over each joint, or better still solder the cables together, heat shrink each individually, then heat shrink over both.