Drive faster.
Or, brake harder
As getting them gone is the only cure.
You have to wonder what’s up with some vehicles — especially big trucks — as the noise can be unreal (crock pot running on inverter?; video games on TV? Cheap refrigerator, etc). I figure it’s 120V being run off 12V in the sleeper, but really don’t know.
No way they could ALSO be using a CB.
I’ve elsewhere written of using coax filters (PALOMAR). Install one at each end or DIY ferrite mobile choke. See my post in thread Beads, Ferrites. They’ll reduce duration & degree of this phenomenon in a satisfying way, besides cutting down a lot of OTHER noise.
IMO, a requirement for a CB used for business is both passive & active noise reduction.
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