Every once and awhile in Visual Studio I am typing along and somehow end up with some type of alternate keyboard turned out. My only way to reset it was to restart Visual Studio. I finally got tired of this, and decided it must be a keyboard shortcut I am hitting by accident. After a bit of searching, I found that ALT + SHIFT seems to change the keyboard culture. I can toggle back and forth with this combination. Seems weird that a such a simple combination would do this, thus why I encounter so often I guess.
Thank you! I was experiencing the same thing and getting quite aggravated.