I now think that these scammers are using the DNC list to acquire numbers to call. I have had my land line on the list for years and constantly receive these robo calls. I recently renewed my registration and added my cell phone. I have never had a robo call on my cell until I registered it on the DNC list. I am now receiving robo calls on my cell phone. Figure it.
After numerous calls without answering, I picked up on a call when I was bored. Eventually he says "Hello? Can you hear me?". I said "No". Silence. then "Hello? Can you hear me?" I said "No". He started talking crap about survey. I looked over at Sweetie and talked over him. "I wish I could hear what they are saying. Must be a really important call. Calls all the time." He stopped his spiel and says, "Sir? Can you hear me?" a little testy and I said "No". He hung up.
Obviously a robo caller because it was blocked by Nomorobo. I've been using Nomorobo since its inception. Nomorobo is now catching almost 100% of those calls that used to get through to my phone. Bless the inventor. Great free product!