DC Offset Blocker/Killer - where to buy in the USA


   I have McIntosh MC8207, the first unit I bought from an authorized dealer came with a loud buzzing coming from the left transformer, and was replaced with a new unit which came with even a louder buzzing. The buzzing can be heard from 8 feet away. Then I was told to have install new 20 amp outlet that has its own isolated grounding.
   That was done professionally by an electrician who installed two isolated 20 amp outlets, two 20 amp circuit breakers, two copper polls for grounding for each outlet, each outlet has its own neutral and power line. After all this done the buzzing sound was still there.
   I was then told to buy a power conditioner which I did (Audio Quest Niagara) which was like $4000 and that did not help. Called back McIntosh and was told that I might have DC offset in my AC line and was told by McIntosh that I would need a DC Offset Blocker/Killer to which when I asked them where to buy one they told me to go on the internet and search to find one, to which I cannot find one.
  This bothers me a little bit, if you as a company think that I have dc in my ac and i need a dc blocker wouldn't you need to sell one as well. I brought this amp to my friends house and it was the same no improvement, so my guess is that he has dc in the ac line as well.
   So If anyone of you knows where to buy a DC Offset Blocker/killer please let me know, but even if this helps kill the buzzing wouldn't you guys think that this expensive somewhat hifi amp/brand should be silent from the factory. I mean this is two units in a row all purchased brand new.

My house is 5 years old, everything is brand new, the whole neighborhood is about 8-9 years old, my electrician says that I have perfect power coming to the house and everything looks fine.

Thank You

tomiiv30
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@jay23

The improper grounding outlet has nothing to do with the Niagara, the Niagara was plugged in different outlets that have nothing to do with the outlet that was improperly added.
Guys I think it is pointless to argue any more on this matter, it is what it is, let’s just say I have bad electricity and as a consumer who paid top dollar to be in the wrong so let be it if that makes you happy, and McIntosh is the best audio company in the world.

All I can say to whoever reads this thread and thinks of investing in this brand or this model in particular just make an educated decision of what you want to do.

Too much disinformation is thrown on this thread that the more we argue the more inaccurate posts are being made which does not help anyone.

This is going to be my last post on this thread..Peace Out!!!
You spend many $$$$ on the equipment yet you cry about spending $ to send to a service center when you probably have a service center near you that you could deliver to.  I have many pieces of McIntosh equipment that have been fault-free for years. 
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