Got a call from this Detroit number:
It was a local survey. They asked me about my radio listening preferences.
They asked various questions regarding the type of radio stations, radio show personalities and music preferences. How often do I listen to them and to radio in general.
Recording said "this is a courtesy call. we'll call back later."
My caller id also said: Detroit MI
I have my phone on the do not call list, just another way to collect phone numbers. If you call the number then you have contacted them and it will be return contact and not breaking any laws. just don't respond or answer any unknown numbers.