I've uninstalled mscim but still have no virtual keyboard and no symbol input. I also have to hold fn and press a key to type the symbols mapped to the keyboard.

Not sure if it's related but I also have text input problems with Media Player. When I type-to-filter the first letter appears normally then a weird box appears in the bottom right of the screen with focus and I end up typing into it. It doesn't do anything that I've noticed (other than appear and annoy me).