From certain time my computer start behave kind of crazy. Sometimes its create a beep sound then when I try to type in search bar its automaticaly write random symbol and goes continualy to infinity. Cant stop it. Unable to write anything to anywhere. After while its disapear. I tried more then 3 antivires programs but didn't find any virus even spyware. I dont know what to do. I'm not PC guru, just regular user and using One Care to protect my PC. Seems like is not enough. Please help, thank you!