Stand by error message

My Inspiron 1525 will not go into stand by either by pressing Fn+Esc/Suspend, or going through the Start menu. I get an error window that says: The device driver for the Conexant HDA D330 MCD V.92 Modem device is preventing the machine from entering standby. Please close all applications and try again. If the problem persists, you may have to update this driver".

I've had this laptop since November 2008 and today is the first time I got the error message.  I have not added any new software since December.  In January we went on DSL so we are not currently using the modem.  We're running Windows XP and is current with all it's updates.

Any suggestions?