I got a new Logitech Wireless Keyboard/Mouse combo. I had a cheaper logitech combo previously. Now, whenever my typing speed gets into a reasonably brisk pace, it adds random letters.

I'm wondering if this is a driver conflict issue between the old and the new.

Do you have lots of other wireless devices around? You could be getting interference when you send a lot of traffic (type fast) and it gets confused.

Personally after having a few different wireless mice, I gave up and went back to wired, better response, lighter, and more reliable. (logitech g15 keyboard and mx 400 mouse).

I've had the same problem. It would also popup the encrypt connection box thingy if i press three or more keys at the same time. I formatted and it has been working just fine without the logitech driver crap.