Inspiron "New Device" alert malfunction

This has happened to me a couple of times, and I don't know how to fix it. My system keeps alerting me that I have plugged a new device into my laptop, but nothing is plugged in except the power cord! Periodically it will alert me that something is being plugged in then unplugged in rapid succession. I can't get it to stop! Any suggestions on how to fix it? I'm tired of keeping my computer on mute so I don't go crazy!