Greg, I wondered the same thing about the jaws being bad or incompatible. I've basically ruled out the incompatible part. That Leaves me with a couple plausible explanations.
A Power line carrier Amplifier,
A Net metering "adapter"
A filter or an arrestor
A damaged socket adapter
There is no antenna at or anywhere close to my service drop, but i don't expect one with power line carrier transmission.
I need to talk to my POCO and see what they say.
Interesting and bothersome that my house is the only place that people can hear it, and i have not read anything about anyone anywhere else experiencing it...