Hooked up the emulated Wiimote speaker.

The Wiimotes are positioned as follows:
Wiimote 0 = Center
Wiimote 1 = Left
Wiimote 2 = Right
Wiimote 3 = Center

The Wiimote speaker output can be disabled via the "Enable Speaker Data" checkbox in the Wiimote settings.
I'm pretty sure you don't need to call .get() in these lines considering unique_ptrs still allow for dereferencing directly.

e.g. http://ideone.com/vk3RVe