Received call and no voice or any noise of any kind.

The phone number is from Children's Hospital at Froedtert / Med. Coll. of Wisc,

Owned by Children's Hospital - but they also have a bill collection group that collects for a variety of other health care providers.  I know, I installed the system and created that number to display on Caller ID so the main switchboard would not get tons of calls from people saying "Did you call me?"

i didnt answer the phone because i'm at work. but ive never seen it before, and thought id research it, to my surprise finding this site, so i thought id report it.

Actually this is the number for Children's Hospital ER.  They use it to call and check on if your child is ok after they have been seen.  I didn't answer and they did leave me a message just wanting to make sure my son was ok.