What can cause ovrHmd_CreateDebug to fail

Hi,

I've written some programs with the Oculus Rift SDK 0.3.2 and everything worked fine.
I ran them with both a 'real' Oculus and the 'false' one, aka created with

ovrHmd_CreateDebug(ovrHmd_DK1)

But here I've come to an unexpected issue: the following code throws the exception:

hmd_ = ovrHmd_Create(0);
  if (!hmd_)
  {
    hmd_ = ovrHmd_CreateDebug(ovrHmd_DK1);

    if(!hmd_)
    {
      throw std::runtime_error("Cannot create the debug dk1");
      
    }
  }

The code for ovrHmd_CreateDebug is quite simple (located in CAPI_HmdState.cpp):

OVR_EXPORT ovrHmd ovrHmd_CreateDebug(ovrHmdType type)
{
    if (!GlobalState::pInstance)
        return 0;    

    HMDState* hmds = new HMDState(type);    
    return hmds;
}

So I suppose

GlobalState::pInstance

is null, but how? why?
Until now I did not bother with any GlobalState::pInstance...


Maybe someone knows the cause of the problem or experienced it before?

Thanks for your help