SimplePlay3DSpatialSoundUWP crashes when changing Spatial Sound setting

[JelleVarjo]

SimplePlay3DSpatialSoundUWP (and potentially others too) crash when the user changes the "Spatial sound" setting from e.g. Windows Sonic for Headphones to OFF. (Also crashes at any other combination.)

Callstack:

SimplePlay3DSpatialSound.exe!ISACRenderer::IsActive() Line 29 C++
SimplePlay3DSpatialSound.exe!`anonymous namespace'::SpatialWorkCallback(_TP_CALLBACK_INSTANCE * Instance, void * Context, _TP_WORK * Work) Line 37 C++
[External Code]

Reason:
Sink->m_renderer in SpatialWorkCallback is NULL.