I have an amp that hums. I've seen other postings for the same problem...but no real viable solutions. I've tried everything..moving it, unplugging equiptment, etc...nothing has worked. I've been told it is "DC build up in the transformer." I've also been told the amp may be defective (the transformer was not wound properly???).

I noticed PS Audio used to offer a "Hummbuster" but they have discontinued. I found a similar product from a company called Channel Island Audio but it costs $300. I really don't want to spend that kind of $$$ not knowing if its going to work. Does anyone know of a product that filters DC? HELP!!!!
Thank you