Why is my Mac acting crazy?

Episode 1329 (1:02:35)

Dave from Hollywood Hills, CA
Apple iMac

Dave feels like his computer is possessed. After awhile, it just goes crazy on him. It's an old Mac and runs OS X Lion. Leo says that the problem may be a messed up keyboard or mouse. A 10 year old mac is long past the time to get a new one and there's new refreshed Macs coming next month. He can also get a refurbished one from Apple and save a few hundred bucks.