For the first two months it was happening, September - October 2012 my wife and I lost several hours preparing for the next event. At a few minutes prior we would take up stations and attempt to pinpoint where the sound was coming from. Unfortunately it was at such a high frequency and so quiet that it was near impossible to hone in on, even with the entire family helping.
Halfway through the first round of this repeating event we began to strategically unplug items, then moved to turning off entire rooms, and finally went with turning off the entire house. The sound continued to occur - every 34 maddening minutes. We researched for cataloged "phenomena" online. The wife asked online friends through networks if anyone had heard of such things. Aside from the re-assurance that we were at least having a mass delusion experience and not just one of us was crazy, nothing was determined.
Then, suddenly near the end of October it just quit. No more sound. My wife and I were relieved. Not thrilled since we had not solved the mystery, but relieved it was gone.
Halfway through November the sound suddenly began again. This time I dug deeper online and found people convinced it is the government testing brain-altering waves or tapping into their brain waves. Honestly I couldn't imagine what the government would want to hear from my brain. ;0) I think they would rather avoid listening to conversations about peaceful people wanting Liberty - kind of a boring topic for a statist. I even downloaded an app to record the sounds from my phone. Unfortunately it never picked up the sound - thus convincing me that 7 people must be going slightly insane. Finally we gave up and began just waving hello to the sound with sweet gestures of the hands.
The good news is that this story has a non-conspiratorial ending. Last night I removed the batteries from my Gyration remote as we had recently replaced it with another Universal Remote that works on both infrared and radio frequency. We no longer needed a remote that could unreliably control a PC. Half-way through our evening I realized I had not heard the sound at all and decided to see if it was the remote. I put the batteries back in and pressed the mouse control button and immediately the gyro inside began producing a high-pitch vibration.
Now the only question remains is why did it go off every 34 minutes for months? The 3 week gap between the regular occurrences is logically deduced as a result of the remote being bumped and re-aligning the gyro such that it would not hum, but run silently as they typically do. The one complaint I've had about the Gyration remotes is that they are easily knocked out of alignment resulting in mouse pointers that cannot be controlled. Now, it appears this can also result in obnoxious noises.