The slow death of our microwave

My microwave is possessed! Last night dinner was in the oven, I was on the phone in the living room, Maddy was watching TV, Connor and Larry were at the store... all was as it should be. Then Maddy came into the room and stood at the end of the couch. I hate to admit this... but I shooed her away. But as soon as she left I realized she had a very odd look on her face. So I get up and go into the family room. Before I can even ask her what she wanted to say I notice the microwave is going. I go over and it's on defrost and has over 4 minutes left to go. I turn it off.

Me: "Did you turn on the microwave?"
Her: "No."
Me: "You didn't touch the microwave?"
Her:"No."

Now, she isn't one to lie so I guess I believed her. What I really thought was that she did it on accident and maybe didn't realize it. That's an awful lot of buttons to push on accident. But like I said, she doesn't normally lie so I just let it go.

So then like 5 minutes later I'm getting plates made for everyone and the microwave just turns on all by itself. I was totally freaked out. So I unplugged it and made the plan that if it turns on while it's unplugged I'm outta here.

This isn't the first time the microwave has misbehaved. Last winter it would get real hot for no reason whatsoever. Even without being used the outside would be hot to the touch. We left it unplugged for about week and then it seemed fine. And I kinda forgot all about it.

So needless to say I'm looking into a new one now. As of this moment we will leave it unplugged unless we're using it, but we're in the market for a new one. Something is not right with it.