Keyboard Problem

I was browsing the web when all of a sudden some letters typed on the keyboard started appearing with weird characters. I'm using the on-screen keyboard to type this. Some letters work properly while others appear with weird characters. The letter g, for example appears like this: [g
The letter p appears as this: pk
Letter o appears as: =o
As I said before, only some letters appear with other characters while others don't. Can this problem just mean that my keyboard is dying or is it a much bigger problem such as virus? Help would be appreciated.

This can be something as simple as a loose plug, or an indication that the keyboard's electronics are failing. I think it's highly unlikely to be a virus - very few modern 'viruses' do stuff like fucking around with the screen or input devices any more.