Head tracking seems out by a factor of 2

Bit of a weird one; if I look straight, things are ok. If I turn my head 45 degrees in the ‘real world’, my in-game Oculus camera rotates by 90 degrees. This only seems to happen in builds. (If I hit ‘play’, I don’t get the expected in-unity-in-dk2 preview I expected; I’m on 5.1.1p2 and SDK 6.0.0.0)

I feel quite ill now - suggestions welcome! (Pretty sure it used to work fine until I upgraded to 5.1.1.p2!

Well, here’s the fix :