The Reason I've Started Rebuking My Microwave in the Name of Jesus

Our microwave has begun beeping at erratic intervals for no apparent reason.  Easy fix, we'll just keep the dumb thing unplugged and enjoy the silence.  Hilarious development: We plug it in, and each electronic beep brings a numeral "6" to the display.
 
Erin, from the kitchen: "Jon, have you seen these sixes appear across the microwave screen?"
Jon:  "Ha, yeah."
Erin:  "You have no power here!  This house is covered in the blood of Jesus.  I command you to get out!"
Jon:  "Are you talking to me?"
Erin:  "No, the poltergeist in our microwave."

Jon says he has a fuzzy memory of once when the microwave stubbornly refused to work, he may have hit the "six" button repeatedly attempting to coax it into action.  This could account for the mark of the beast that has arrived in my kitchen.  Now, if the fool thing starts beeping and sixing while unplugged, then we know we've got a problem.