All at once, my Bluetooth keyboard has stopped sending "home", "page up" and "page down." Strangely, it DOES send "end."

WTF???

Hmm. It happens for my USB keyboard to, so I don't think that it is related to the fact that since, the latest OS upgrade, there are long series of out-of-control key repeats.

WTF?????

I would REALLY like to solve this problem (and the key-repeat issue) as typing is now very awkward. Is anyone else experiencing this?

Do you keyboard Gurus have any theories I can use?