Recieved call from this number. I called it back, it rang and then went to busy signal. I called it back again and this time it said the number was no longer in service.
They called and when the answering machine came on they hung up. I think after reading the above messages left here that this was someone checking phone numbers to see if they are viable and then they sell that information to scammers.
Caller ID said "CBK". I answered, but said nothing. Apparently a collections agency. Since I don't owe anyone but my bank any money, they must be angling to collect on someone I know.