Currently it behaves just like a normal device except contexts are only
processed during calls to alcRenderSamples. Additionally, the ALC_SYNC and
ALC_REFRESH context attributes are not valid for these devices, and there are
two new context attributes to specify the rendering format: ALC_FORMAT_TYPE
and ALC_FORMAT_CHANNELS. These each take one of the type and channel enums
added.
This stuff is subject to change.