We get calls from a number that shows up on our caller ID as 161-782-6611 at least once a day & sometimes 3 & 4 times a day.  It cannot be blocked with call blocking because we are told it is an invalid number.  We have tried answering it & we either don't get any one at all or it sounds like a group of people all talking at once but not saying anything other than "hello" or "hi".  It is getting very frustrating & we can't stop the calls!  Anyone else with this problem or have any ideas?