Since Held_to_Ransom was banned, I guess I'll answer for him. Sound waves can be regulated just as radio waves are if they interfere with something inside your property (or outside). The FCC would decline to regulate in your case because you are not providing a service that is being interfered with. Even if you did your outgoing calls would not be impacted. Even if they were, there are numerous work-arounds to avoid the need to regulate.
But the bottom line is spectrum is not property, therefore this isn't trespass.
LOL.
That is pretty much the same thing as saying that air is not property, which I agree with, but has nothing to do with the issue because it's not the medium, it's the place the medium ends up. The spectrum is not propery, but my telephone is my property, and if I don't want your voice in it, then you are "verbally trespassing". But there are more creative ways to deal with telemarketers than with more legislation.