My PC has developed a strange problem. I can be typing into a text window (like this one or Notepad) and suddenly my input stops appearing and I hear a tinny tone for each key press. I notice that the colour at the top of the window goes paler as this happens. Also if I am scrolling down a list on screen using the scroll wheel on the mouse it stops responding. The mouse pointer continues to move OK.
This is happening roughly every 50 seconds. I can restore input simply by left-clicking but then it will recur 50 secs. later. My keyboard is wired PS2 but I have a wireless mouse. I'm using Windows 7 64 bit.
Can anyone offer a solution.