Managed to answer the next time they called, but they disconnected as soon as I answered. I called them back and got a fax tone so loud that it damn near burst my eardrum!
It's definitely some kind of harassment call (I'm guessing from I.C. Systems, a collection agency for Washington Mutual)since they called 4 times between 6pm and 7pm--while I was busy making supper and couldn't answer the phone. I put the number on my CALL REJECT list.