on the distorted channels of my brand new H&K Switchblade 100w amp i pick up some AM radio that plays zideco and mexican music. how can i stop this? i also get it on my line 6 spider whenever i use my wah pedal. note that the cabinet i just bought... no refunds no returns... was built some time in the late 80's early 90s by mesa boogie. however, i tested it out with a different head and there was no funky radio. i am thinking A the ground in my apartment is not good... or B the head is not good. i bought it "blemished" and i rly hope this isn't the blemish how frustrating!