I have recently started working on an XAudio2 driver for NeLSound, which will allow OpenNeL to make use of Microsoft’s new XAudio2 sound library (included in the latest DirectX SDK), in addition to the three sound libraries already currently supported by OpenNeL (FMod, DSound and OpenAL). The project currently does not implement all functionality yet, as the rest of the features will be implemented in the coming weeks, but it already runs the sound_sources sample included with OpenNeL pretty nicely without problems. The code can be downloaded from http://nel.svn.sourceforge.net/viewvc/nel/trunk/nel/src/sound/driver/xaudio2/, and is released, like all other available OpenNeL code, under version 2 of the GNU General Public License.