Have you checked to make sure your account info isnt being used for something else.. like maybe someone is writting bad checks on your account?
Lately around here many banks have asked clients to go in and change their bank cards and pin numbers because apparently a local store has been found to be selling this information.. and its a big chain store.
I was also called by my bank to change my card because I used it at an atm where a video camera was setup to record my pin number.
Good thing there is more than just one bank to chose from
Wonder if they are putting a mark on your credit rating?