Ingineer said:
This might be an interaction between the car and some equipment/appliance in the house. That's one explanation of how it could move with him to another house.
It could also be a poorly designed power supply in the audio system. There are plenty of these out there!
-P
For what it's worth, it's not just a single piece of gear that exhibits the noise. I think I inventoried the equipment earlier in this thread but it's a set of Harman/Kardon Soundsticks, an Apple 24" LED Cinema Display (it has built-in speakers), and a Sony ES receiver/amplifier -- basically any speakers powered from AC. It's readily apparent with the Soundsticks and the display's built-in speakers but only noticeable from the Sony amplifier if I go right up to the speakers and listen for it. Anyway, I stopped looking for more sources once I saw it was happening with various gear.
[Update: It's worse at the new home. It's louder at my computer speakers but I also just discovered this evening (as the car started charging on an after-midnight timer) that I can hear it from my home theater speakers without going up close to the speakers now *and* I now hear the buzzing from my projector, a JVC RS-1.]
You may recall that the noise also emanated from the electrical panel itself at my old condo -- it does also at the subpanel in my new home. Speaking of which, my new home is only five years old.
Note that a number of things have to be true for this issue to be heard by Nissan:
1) The vehicle must be one of the older LEAFs as supposedly the updated EMI filter was already shipping in newer vehicles in June.
2) The owner has to own and make use of certain powered speakers *while* the vehicle is being charged. In other words, they don't primarily charge overnight while they're sleeping. Also, it's unlikely I would have ever noticed the problem with my Sony receiver/amp if I had not gone looking to see what other gear was affected.
4) The vehicle has to be charged at 240V, not merely 120V.
5) The owner has to be the type of person to notice such low-level noise. (Good hearing and in a quiet environment.)
6) The owner has to care enough about this noise and be motivated enough to actually report the issue to Nissan -- not just mention it on a web forum. This is the kind of issue that I can imagine plenty of people just opting to ignore. Now if the car broke down or if this damaged devices... then there'd be some noise! ;-)
So my frustration lies with Nissan withholding the updated part that I already know solves the problem -- at least for my equipment. Just give me the part please! (Well, and install it too, please. ;-))