[dedward]

What you are hearing is plain old sound - higher frequency, in the ranges we tend to lose first with time and age. In both the TV and light fixtures, you are hearing the transformer coils physically shifting.

I hear them too.

Tooth fillings and bone conduction could pick up AM signals, because of the nature of AM.

[steve19]

Getting older and losing these frequencies has been a blessing. Switch power supplies and old school LCD screens (or the switching power supply used to power them), like those on my palm pilot and other electronics used to really bug me when I young. I am sure modern LED light fixtures would have driven me crazy.

I am sure I cannot appreciate music as well, in fact I have sold almost all my high end audio gear, but I will take the lack of high-frequency sounds in everyday life over slightly better range when listening to music.

[eropple]

I have Hue lights in my house and can't hear them. But I can hear CFLs and it's piercing.

[tzs]

I'm not sure they cannot also do FM. The argument I usually see against FM is that demodulating FM is much more complicated, but that is not really true. Demodulating FM accurately is much more complicated, but if you'll accept a fairly distorted result then an AM demodulator can be used to demodulate FM.

You just tune the AM demodulator off center from the FM signal. This is called slope detection. If you have an SDR you can play around with this. Here's an article on slope detection [1].

I think this only works if the bandwidth of the AM detector is fairly small compared to the FM signal. I have no idea what the bandwidth of tooth filling receivers is.

[1] http://www.radio-electronics.com/info/rf-technology-design/f...