What is the sound I am hearing Has anyone heard of anything like this
The sound is a lot quieter, but it is still there. It may be that you also hear higher frequencys than most people.
The frequency you hear is about 15KHz and above. Many women can can hear in that range, but usually not men.
You may have a high frequency range response. I'm also sensitive to high frequency sound, but not lower frequencies.
In addition to the fly-back transformer, you can also hear a "buzz" when a graphic is on screen because the video signal "bleeds" into an out of tune sound circuit. Likewise, if the video circuit on a monitor is out of tune, or failing, you'll hear a buzz.
Don't know about air fresheners. Don't have one.
The walls in your room reflect and mix the noise. If you move your head around, you should notice a difference in intensity from position to position. This is due to constructive and destructive interference.
Think about it this way. When you drop a stone in a body of water it creates a wave pattern. Now, drop another stone and watch the waves interfer with each other.
When crest meets crest, they create a larger wave. When crest meets trough, they cancel.
.....