This is another dumb newbie problem. I am using a small Peavey practice amp with a Ibanez BTB 515 and a cheap cable. With BTB volume and treble set at reasonable settings (say 9PM) and the Peavey at no more than 11AM, there is a very annoying hissing/buzzing sound that gets worse when no fingers are on any strings. Is this just a fact of life, or is something in my signal chain hosed? Peavy has a 3 prong plug, BTW.