Hi All

I wonder if anyone else has had this issue and knows how to fix...

I'm typing normally in a window. It could be in any application (any MS Office app, Skype, etc; but curiously NOT internet explorer). I press the 1 key (this only happens with the 1 key - alone or SHIFT+1, CTRL+1, ALT+1) and the whole window instantly shifts position on the desktop down and to the right. This typically moves the active window partially off screen (and of course mostly such that the text I'm typing also goes off screen).
Interestingly it also moves the mouse position too - say I have the mouse cursor arrow somewhere inside the active window, the cursor also shifts position to be in the same position relative to the active window.

The move only happens once (i.e. if I press 1 for a second time or more, the active window doesn't move again).

It happens both when the active window is maximised and when it is not (when it's maximised the active window changes to 'restore down' status and I think the new position of the active window is always the same and the active window also changes to the same new size too.

Anyone have the slightest clue what might be going on here?

[This is happening on my Surface Pro 3 i7 with windows 8.1, not any of my other PCs]

Thanks a lot