Visual Studio keyboard layout swaps from UK to US

Solution: Hotkey is Shift+Alt

I've been having problems in Visual Studio where my keyboard would suddenly swap from UK to US layout. From that point on the " key would map to @ and vice versa.

I eventually got round to googling the problem and came to this Microsoft connect item: http://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?FeedbackID=269947

So I learn that there is a hot key - Shift+Alt - that does this and so the problem is reversable. But I have to agree with the person who sent in that item. Why does this hot key exist or perhaps why is it such a simple combo? The only thing I can think of is that MS people testing VS wanted this. To me it is just a pain.