Keyboard doesn't keep up with typing

I'm assuming this is a wireless keyboard - these things are usually the result of one of two things (Besides simply being a poor quality keyboard):

1) Low battery - Try placing fresh batteries in your keyboard.

2) Interference between keyboard and receptor - Ideally, they should be placed on the same surface at the same height, with nothing in between them to block the signal. If your receptor is not on the same level as your keyboard, this could definitely cause problems like the one you're describing.

Try it, hope it helps.