This is NOT a washington mutual number. This is a scammer trying to get you to call back and give your credit card information. Do NOT do so! Wamu denies any association with these people.
multiple calls from this number in December, every 7 minutes some days. I am a WAMU customer, but have no debt with them or anyone else, so it is definitely not collections.
It sounds like some folks have called back and been directed to a recording that identifies itself as WAMU and asks for your credit card information--- OBVIOUSLY A SCAM if that is the case.