They called twice.  Left a message on my answering machine once, but it was just fuzzy noise.  Today I picked up on the 3rd ring and it was just fuzzy noise again.

I did a search of the number.  I'm not going to PAY to find out who they are.  My phone number is on the DO NOT CALL LIST.  

Does anyone know who they are?  Are they highjacking our phone numbers for illegal purposes?  (When I worked at a hotel, some people would try to connect with our line somehow to get free long distance (for them). We had to hang up on them within 11 seconds to prevent them from highjacking our line.)